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What's the Coolest Thing You've Ever Built?

Cliff posted more than 7 years ago | from the something-you'd-never-forget dept.

Hardware Hacking 535

Josh Lindenmuth asks: "In high school I was involved in an engineering competition where we needed to create a machine that could move 100 lbs of groceries from a disabled person's car up and down a set of stairs, and then into their kitchen. It was probably the coolest thing I ever built (there were only 3 of us on the team), even though the wooden treads started splintering halfway up the stairs (we didn't have a metal shop, so it was made entirely out of wood, spare boat parts, and conveyor belts) and then it completely destroyed the stairs on its way down (it weighed over 300 lbs)." That's Josh's story, now he wants to know yours. Cool computers, cars, hovercraft, handheld devices, fusion reactors — what is the most interesting gadget, product, or device that you've ever built on your own?

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My Son (5, Funny)

Anonymous Coward | more than 7 years ago | (#17080374)


Re:My Son (4, Funny)

Anonymous Coward | more than 7 years ago | (#17080486)

Mod parent up! HA HA! Really! Parent! Oh, pinch me!

Hope he's smarter than his parents! (0, Troll)

FatSean (18753) | more than 7 years ago | (#17080488)

Because, even if you were his mother, you didn't 'build' him any more than you 'built' that giant corn-speckled turd you just dropped off!

Re:Hope he's smarter than his parents! (1)

Der PC (1026194) | more than 7 years ago | (#17080574)

Of course, if the son is a clone of his parent and he grew up in a test tube, the parent can claim to have "built" him. And that would actually be a pretty darn cool thing to have done ;)

Re:My Son (4, Funny)

Fulkkari (603331) | more than 7 years ago | (#17080490)

Built? If you are the average Slashdotter, you merely did half of the design.


Getting that far can be already be seen as a great accomplishment over here. :-)

Re:My Son (3, Funny)

Anonymous Coward | more than 7 years ago | (#17080610)

If they are the avarage slashdoter, i think they did more then half, like all of it. Its no secret that its hard for us to find a partner to perform this activity, so, some rare slashdoters must have evolved to a point where they can do all the work themselfs. This is proof of evolution in action.

Re:My Son (1, Insightful)

Ucidalin (936551) | more than 7 years ago | (#17080856)

Well, last time I checked, there was no building in child making. You pretty much just donate a seed and fertilize it, then just nourish and protect it. Nature does all the building here. Maybe when DNA research advances, you can actually build your child. Till then it is Nature that does the building. A woodchuck would chuck as much wood as a woodchuck could chuck if a woodchuck COULD chuck wood.

My Son My Period. (2, Funny)

Anonymous Coward | more than 7 years ago | (#17080648)

You built a period into your son? How freudian of you. I hate to see what you put into your daughter.

Re:My Son (2, Funny)

waterford0069 (580760) | more than 7 years ago | (#17080860)

At worst you provided half the design.

At best you provided half the design, the manufacturing space, the materials distribution chain, and the delivery system. Your son did the rest him self (which when you think about it is rather resourceful of him).

However, this being Slashdot - I'd bet on the former over the latter.

SP (-1, Offtopic)

Zebaulon (534793) | more than 7 years ago | (#17080380)

Second Post!
yadda yadda biji bubu

I gots you all beat (4, Funny)

Quiet_Desperation (858215) | more than 7 years ago | (#17080384)

I built a reality simulator. You're living in it right now. Neat, huh?!

Re:I gots you all beat (4, Funny)

hotdiggitydawg (881316) | more than 7 years ago | (#17080806)

No, it sux bigtime. The plot moves at a glacial pace. Why do you think we're always trying to escape it?

Stealth Roach-Clip (1)

FatSean (18753) | more than 7 years ago | (#17080388)

I had a fancy Williams-Sonoma aluminum cork screw and bottle opener. It was a flat oval and the end opposite the bottle opener hook split open like wings. The wings revealed a cork screw, which was yanked out of the gizmo the third time I opened a bottle with it.

So, a little epoxy and an old aligator clip...I have a stealth bottle-opener and roach clip.

Was also involved with 'Odyssey/Olympics of the Mind', but that was lame because every team had parental help and the money rules were shat upon constantly.

That one time (5, Funny)

pap3rw8 (962737) | more than 7 years ago | (#17080390)

There was that one time I built a machine that could propel cats to the moon. It almost worked, too.

Re:That one time (4, Funny)

ArsonSmith (13997) | more than 7 years ago | (#17080676)

Is that why I found a dead cat in my back yard yesterday?

I hate to (have to) ask... (3, Insightful)

davecrusoe (861547) | more than 7 years ago | (#17080392)

but... how could a 300 pound machine completely destroy stairs... because of its weight? For what it's worth, I imagine that many of us weigh > 300 lbs when carrying our MASSIVE computers upstairs from the car... or 130 pounds of Ramen noodles... or about 60 of the lastest video games... or... well, you get the point.

Re:I hate to (have to) ask... (4, Funny)

setirw (854029) | more than 7 years ago | (#17080440)

I think many /. readers weigh >300lbs, period.

Re:I hate to (have to) ask... (3, Insightful)

stevo3232 (794498) | more than 7 years ago | (#17080450)

It's all in how it's going down the stairs. A 300 pound person walking down the stairs and barrelling down the stairs are two different things.

Re:I hate to (have to) ask... (1)

Provocateur (133110) | more than 7 years ago | (#17080512)

I always go like they do in the movies, as if somebody pushed you from behind. More fun that way, you get to say a line when you get back up.

Re:I hate to (have to) ask... (0, Offtopic)

Mr. Underbridge (666784) | more than 7 years ago | (#17080458)

Or timothy with 200 lbs of gay scheisse porn?

Damn, I wish he was still an editor here.

Re:I hate to (have to) ask... (5, Funny)

Anonymous Coward | more than 7 years ago | (#17080480)

Feet tend to distribute wait in a nice, convenient way. That, added to the fact that muscles allow us to slowly descend our feet to contact the step. A 300lbs robot composed of wood, probably does not have this feature. Plus, wood is much harder than flesh (duh). Get a 300lbs pirate with wooden pegs for legs and watch him fuck up your stairs in a few weeks.

Cool! (4, Funny)

jrobinson5 (974354) | more than 7 years ago | (#17080520)

Where can I sign up to order one of these 300 pound pirates with peg legs?

Re:I hate to (have to) ask... (1)

Viraptor (898832) | more than 7 years ago | (#17080546)

Now imagine, that you're hard as a piece of wood (stop thinking what I'm thinking), have no suspension (legs) and that you weight 300 pounds (not that I have any idea how much that is in your strange system - grow up people - start measuring weight in stones, like the rest of us in Drakalor Chain).
Now throw your imagination on the stairs from about 1,5m (that's 4,92125984 feet for SI impaired) - I'm sure there was a big chance, that your imagined stairs either were destroyed (wooden), or some chips fell off (stone).

Re:I hate to (have to) ask... (1)

fotbr (855184) | more than 7 years ago | (#17080786)

Thanks, but we SI impared people don't normally use decimals when measuring feet. We inherited this goofy unit called "inches".

And 300 pounds is a bit over 20 stones, if that helps your imagination any.

Re:I hate to (have to) ask... (4, Funny)

Chris Burke (6130) | more than 7 years ago | (#17080660)

I don't know, but I'm thinking he'd view his project as much more of a success if he simply re-defined it. Machine for carrying groceries up stairs? No! Automatic Staircase Destroyer? Hell yes!

Re:I hate to (have to) ask... (0)

Anonymous Coward | more than 7 years ago | (#17080784)

Simple answer: Humans aren't mechanized.. And usually have softer more gentle conveyorbelt robotics on their lower extremities :P

While in my engineering college ... (2, Interesting)

Utopia (149375) | more than 7 years ago | (#17080396)

... I build a radar.
Now I don't build cool stuff I just write code.

Ronja project (2, Interesting)

Anonymous Coward | more than 7 years ago | (#17080428)

I have built Ronja Optical Datalink (FSO) according the instructions on the homepage ( [] ). It's amazing to build a wireless network device on your own.

Mine (5, Funny)

iamdrscience (541136) | more than 7 years ago | (#17080434)

One time I made a "Jump to Conclusions" mat. You see, it was this mat that you would put on the floor... and had different conclusions written on it that you could jump to.

Re:Mine (1)

antiaktiv (848995) | more than 7 years ago | (#17080470)

I once made a twister mat that covered an huge basement for a party. That was a really rockin' party.

PVC pipe. (-1, Troll)

Anonymous Coward | more than 7 years ago | (#17080438)

I once stuck some 2.5" diameter PVC drainage pipe up my wife's pussy as an improvised dildo.

Re:PVC pipe. (0, Funny)

Anonymous Coward | more than 7 years ago | (#17080508)

I once stuck my dick in 2.5" drainage pipe as an improvised version of your wife's pussy.

An airplane. Still working on it... (3, Interesting)

scsirob (246572) | more than 7 years ago | (#17080456)

I'm building a RANS S6S Coyote airplane, together with a friend. We're six years and counting, with just a single evening each week. Yes, it takes *forever*, but it's truely amazing to see this pile of aluminum, steel and pop rivets slowly transform into a real plane that I can take for a spin. 2007 should be the year...

Re:An airplane. Still working on it... (1)

Chairboy (88841) | more than 7 years ago | (#17080636)

I'm also building an airplane, a Cozy Mk IV (a 4 seater version of Burt Rutan's LongEZ).

Airplanes are very fulfilling projects, well suited for this crowd.

Re:An airplane. Still working on it... (1)

worst_name_ever (633374) | more than 7 years ago | (#17080688)

RV-7 here. And since I'm posting on /. you know my panel will be geek-pimped out!

Re:An airplane. Still working on it... (1)

MadEE (784327) | more than 7 years ago | (#17080836)

I have been interested in that craft. How much has it cost you and how difficult has the construction been on that model? Any other weirdness?

Biodiesel Reactor (5, Interesting)

Anonymous Coward | more than 7 years ago | (#17080466)

My first semester at UW Madison my Introduction to Engineering class buit a BioDiesel Reactor. It was 18 freshman students who knew nothing about biodiesel, and by the end of the semester we designed and constructed the reactor. I was involved on the team that designed and executed a safety system that monitored the temperatures inside the reactor tank, if the temperatures exceeded 60 degrees celsius a relay shut off the heating element in the reactor. This was one section of a larger lecture, and all other projects pailed in comparison. We also had a $500 budget which we exceeded by $4500, the project was paid for by a department at a technical school in Madison.

amstrad Teletype (3, Interesting)

CdBee (742846) | more than 7 years ago | (#17080482)

Back in the 80s I had 2 Amstrad CPC464 personal computers (Z-80 CPU, 64k, tape deck built-in). I built an electronic circuit to link the joystick port from one to the sound-out port of the other (sound triggered a switch-effect using transistors)

I wrote Morse-code modulator/demodulator software and set them up as a simple text-based comms system down the garden...

Success!! (0)

Anonymous Coward | more than 7 years ago | (#17080494)

He views his device as a failed stair climber, I view it as a successful stair destroyer.

Mission Accomplished!

A custom kernel (1)

bogaboga (793279) | more than 7 years ago | (#17080498)

The coolest thing I ever did was build my own custom Linux Kernel. It was way back in the year 1999 when the process was not that straight forward. My distro was called `Bogaboga Linux' and is still available on a 486 system.

Re:A custom kernel (1)

Short Circuit (52384) | more than 7 years ago | (#17080812)

If you're up for the challenge, building your own kernel is again no longer simple on some distros. Sure, if you're running Debian, stock kernel sources from will do, but if you're running Ubuntu, well, God be with you.

When I ran Debian, I'd download the latest sources and compile them, just to play with the new features. I started using the 2.6 kernel tree at 2.6.0-test1, to see what all the hype about the O(1) scheduler, was.

Air conditioner (1)

maGiC_RS (946022) | more than 7 years ago | (#17080510)

I built a makeshift air conditioner using 12 40mm case fans from old computers, a barrel (so the fans blow air through cold water) and a 220V to 12V inverter.

Couple of things (3, Interesting)

tompaulco (629533) | more than 7 years ago | (#17080514)

When I was about 11 or 12, I helped my dad build a Z80 based computer. As far as what I have done one my own (although the article had three people), all of my early exploits were software based. When I was around 13 I wrote the entire game of Monolopoly on a TRS-80. A few years later, since I couldn't afford Tetris, but I had seen how it worked, I wrote Tetris on my very early PC.
Nowadays, I build more hardware stuff, but it is not as cool because I am an adult and should know how to build it. For example, I built a 180 gallon saltwater reef tank with an oak cabinet, aut water replenisher, Carbon doser, protein filter and all kinds of other accessories, and plumbed the sump down to my basement.
A few years back, I built a 20X40 swimming pool with diving board and slide, and built a 70X40 concrete deck (yes, I mixed and poured it myself) with cedar railing to surround it.

A monolith (1)

JelloCube27 (901060) | more than 7 years ago | (#17080524)

I built 9-foot-tall monolith out of wood once. I put it in my school woods and, to the best of my knowledge, it's still there

Re:A monolith (2, Funny)

l810c (551591) | more than 7 years ago | (#17080662)

My senior year at high school, we were supposed to build a float for the high school parade. Instead, we built a 10 foot high paper mache penis and placed it on top of the school right over the principal's office.

Re:A monolith (1)

snooo53 (663796) | more than 7 years ago | (#17080682)

How did you transmute the wood into rock? This sounds suspiciously like a totem pole...

Re:A monolith (1)

cool_arrow (881921) | more than 7 years ago | (#17080690)

No it's not. I chopped it up and used it for firewood;) Just out of curiosity, why did you build the wooden monolith?

an IM client on a TRS-80 (5, Interesting)

AWhistler (597388) | more than 7 years ago | (#17080532)

With a friend I built and wrote an IM client that worked between two TRS-80 model I computers. We "networked" them together by connecting the tape drives between each other (needed an amplifier), and cross connected the "send" and "receive". Then we wrote software that accepted input, sent it across the tape drive, then listened for a message from the tape drive.

It worked well, but of course was very slow.

Then there's the joystick-controlled typewriter...but that wasn't as cool.

Re:an IM client on a TRS-80 (1)

AWhistler (597388) | more than 7 years ago | (#17080602)

Oh yeah. I saw a friend write a space invaders game in the built-in BASIC, so I proceeded to learn how and wrote one myself. That was a neat trick since the TRS-80 was too slow to do real-time games without assembly code, but it worked well. That was pretty cool at the time.

I would have to say (1)

Centurix (249778) | more than 7 years ago | (#17080534)

Purchasing a Sinclair Research ZX80 in kit form, assembling it and making it work first time.

Outside of computing, I've rebuilt a 1969 Datsun 240Z (with chrome badges on the pillars, Japanese import into Australia). Lesson learnt? Next time, make sure the body/chassis is in better condition before starting. I've learnt to hate panel and general body work. Sold for a loss, but made up for it in learning.

* ft tall water balloon slingshot (3, Funny)

Registered Coward v2 (447531) | more than 7 years ago | (#17080536)

We were the terror of Fraternity Row. It used steal pipe and multiple pieces of chem hose - after a little practice we could lob a water balloon through an open window hundreds of feet away.

Burningman (2, Interesting)

Anonymous Coward | more than 7 years ago | (#17080544)

You want to see some neat engineering? Most is not practical at all which means it's all that much more awsome. Go to Burningman []

And who do you work for now? (0, Troll)

xxxJonBoyxxx (565205) | more than 7 years ago | (#17080554)

It was probably the coolest thing I ever built...even though the wooden treads started splintering halfway up the stairs and then it completely destroyed the stairs on its way down."

And who do you work for now?

I'm guessing NASA or the Army Corps of Engineers...

A partial computer! (5, Interesting)

IversenX (713302) | more than 7 years ago | (#17080558)

As a freshman in the danish "gymnasium" (which is senior year of high school + 2 years of college), we had
an project in physics class where we could write about anything we wanted to. As a group of three students
we chose to write about digital logic. In the beginning, we only planned to write about digital logic theory,
circuit design theory, and so on, but we soon realized we wanted to build an actual circuit design.

After spending days or even weeks designing the thing, we finally had our ÜberMachine - we called it the
DALO (Digital Arithmetic and Logic Unit). It was essentially an ALU with support for addition, subtraction,
logic "or", logic "and", and logic "not".

Now, in this day and age of computers, it would take most programmers just a few minutes to make such a program
in most programming languages. But this was done entirely in hardware, with no fancy integrated circuits! We
used about 15 simple chips (classic phillips 74xx-series), which only contains or, and, not and the occasional

For the input, we used manual flip-switches, connected directly to the input legs on the microchips.

For output we used a series of LEDs to output each of the 4 digits in the A-input, B-input and the result. At
the same time, we used a classic 7-segment display for each, driven by a 7-segment-decoder chip.

In the end, the things actually worked, which was quite amazing to see. We hadn't received any formal training
in digital logic, electronics, or circuit design - and yet it worked. The entire machine was soldered with more
wires than I ever wish to see again, and it took a lot of blood, sweat and... time - but we did it!

Some years later, I was employed as a teaching assistant at the university. One of my classes were in machine
architecture, a course which most students couldn't see as relating to reality very much, because they didn't
believe anybody except large companies could build computers or circuits. On the day of my last class, just a
few days prior to the exam, I brought our high school project with me, and showed them how it was built.
Several of them were amazed by it, and it really seemed to make a difference. Computers were no longer magical
devices crafted by dwarven builders, they were simply complex machines, free for anybody to build.

That's the greatest thing I have ever built. Now, if we were talking about programming, that would be
another matter... :-)

I helped to build.. (1)

Null537 (772236) | more than 7 years ago | (#17080564)

...four robots over 4 years while in high school for the FIRST Robotics Competition [] . The first two years they were completely human controlled, the next to (and every year sense) there has been a time period of automation before human control takes over.

Telescope (1)

Average_Joe_Sixpack (534373) | more than 7 years ago | (#17080568)

6" mirror grinding kit from Edmund Scientific (God I miss that store), purchased secondary and rack & pinion focuser. The rest was scavenged. It was pretty neat at low powers, but no where near as good as a cheap dept store scope today.

A robot that can traverse staircases (3, Interesting)

drgroove (631550) | more than 7 years ago | (#17080584)

I built a robot in jr high that could walk up and down stairs. The robot had two legs, w/ four feet, two on each side. Each leg was bound to the robot's body using a turning motor in the center of the leg (which was really just a tubular pipe about 1 ft in length). Each leg had one foot on the end, which had a flat, circular surface that was adjoined on a small 1" pipe, attached to the end of the leg. The feet could spin freely at the endpoint of the leg. So, when the legs spun, the feet rotated around. Gravity moved the feet flatly towards the floor. Walking up stairs, the robot would have two feet on the current stair, with the next two rotating upwards or downwards towards the next stair. I built in a little button on both sides of the robot's body that would alternate the direction of the leg motors, so when the robot got to the top of the stairs, it would bump the wall, change direction and walk back down. About every 3 weeks I'd change the batteries and put it back in action. Pity my poor parents, having to walk over my robot anytime they wanted to go up or down the stairs for about 3 months!

A 'clue meter' for the office (1)

nurb432 (527695) | more than 7 years ago | (#17080586)

Too bad i cant get it to move off zero, must be a flaw in it somewhere....

Not Cool (2, Informative)

camperdave (969942) | more than 7 years ago | (#17080592)

I built my own computer, but it's not very cool. In fact, it can get quite warm at times.

Nixie tube display for a computer (5, Interesting)

Alioth (221270) | more than 7 years ago | (#17080614)

A few months ago, I started learning electronics. My first project is (electronically) complete - it just needs some finishing off to the housing.
It's a Nixie tube display, with 7 nixie tubes. I built an RS-232 reciever/sender out of 4000-series logic ICs (not a CPU or microcontroller in sight) - mostly counters and registers, and a few AND gates and inverters.

Pictures of the project's progress are at [] (two pages of photos - the working project is on page 2). I've also kept a journal of building and learning in my Slashdot journal.

The hardest part of it was probably getting the 170 volt switch mode power supply to work correctly (mainly getting it to regulate) and not put so much noise back into the 5 volt supply to cause latches and registers to lose their values. Some help from the NEONIXIE-L group on Yahoo was invaluable here, and I now have a decent 170 volt supply.

I'm now learning how to make things with microprocessors, and once I've done some breadboard experimentation, my next project is to build a logging weather station for the glider club, using a Z80 processor, a flash EPROM, some RAM and probably compact flash for mass storage (not that it'll use a lot of it!), and a small graphics LCD module for display. Currently, I'm at the stage where I've breadboarded a very basic Z80 system that can output values on a crude output device. But it works!

Re:Nixie tube display for a computer (1)

rbanzai (596355) | more than 7 years ago | (#17080680)

Great pictures! I love nixie tubes though I've never done electronics. I just like the look of them. It's nice to see the "ugly" electronic truth behind all these lovely pixels.

Re:Nixie tube display for a computer (1)

nowhere.elysium (924845) | more than 7 years ago | (#17080794)

That is *incredibly* cool. Kudos to you :D

New molecules... (1)

westcoaster004 (893514) | more than 7 years ago | (#17080634)

Well, being a chemist, making a few new molecules [] in my undergrad thesis was a very cool thing to do, of course now I have to do it all the time, but every once in a while you make something really cool.

Lego (1)

Ant P. (974313) | more than 7 years ago | (#17080638)

The coolest thing I've probably built is still the car thing I stuck together years ago out of technic parts, with a moving engine block and weird cantilever suspension. I lost it somewhere :(

Mindstorms (1)

quique h. (938286) | more than 7 years ago | (#17080844)

Six years ago, back in the ninth grade, I built a LEGO Mindstorms robot for the school science fair. It was very simple, and I made it one afternoon while bored. It cut bananas.

I'd peel the banana, and using a huge knife I tie wrapped to a piece attached directly to the motor axle it'd slowly move along the length of the banana, dropping the weight of the knife onto the banana several times, chopping it into small pieces.

It actually won first place too!

It's actually kind of unimpressive, but then again, so is my life...

A mountain bike (1)

zogger (617870) | more than 7 years ago | (#17080650)

Before there were mountain bikes. I built a fat tired low geared 10 speed in the mid 70s. Had to cut and rethread the spokes to make a rear wheel with a box frame config so caliper brakes would work, then build caliper mounts for the brakes, etc, etc. I was doing a lot of off road bicycling then and kept destroying regular skinny tired wheels and got tired of it, so set down and heavily modified a one speed bike. It was gosh darn spiffy, tell ya what, every biker who saw mine wanted one. There wasn't anything on the market like that at the time, that I was aware of anyway. I've built other stuff I was proud of, but they were more in the biological field, I called them living sculptures, using wired together trees, etc, but the bike was the most hard-tech thing.

Memory card for my ZX-81. From scratch. (0)

Anonymous Coward | more than 7 years ago | (#17080656)

I didn't want to pay the what, $200 for a 16MB memory expansion card (box) for my Sinclair ZX-81 computer and somehow imagined that my time to create it on my own would be worth less than $200. Too much partying, I know.

I ordered 16Mbx1 chips from someplace or other - might've been the local electronics store (emember when they had those? No kids, I'm not talking about Best Buy...), got the National Semiconductor databook and had a look into what it'd take to get the RAS and CAS lines hooked up, etc.

Since I was living in a college group flop in Columbia, S.C. and was close to broke anyway, I didn't want to get into printed circuit boards and so I made the whole thing on blue .1" perf board (yes kids, chips really did use pins on .1" centers...God I feel old...).

This is where the problems set in. First, I was not the greatest at soldering, and didn't have much in the way of soldering tools anyway. These skills would not set in for a few years. Besides that, I was using point-to-point wiring on a device that could potentially be affected by impedance issues, propagation delay and the lot (yes, even at the maybe 1MHz they were clocking this processor).

I managed to saw down a PCB connector I found at a Radio Shack or someplace into something that would fit onto the back of the ZX-81 and managed to jam in a chip of breadboard to make a key so I could get it on straight.

I got the whole thing assembled, plugged it in and...well, it didn't quite work. But it did, kinda.

I think the memory was recognized, but didn't work quite right. I wrote some machine code to do a memory test and page through the thing. I could store and retrieve values, but not reliably over time. Probably some refresh problem. I never did get it to work, deciding instead on gainful employment and purchase of a 2MB chip which I hacked into place on the motherboard.

This is pretty much the closest I've gotten to building completely from scratch for things more complicated than a power supply or op amp circuit. I usually have recipe schematics to go by on other stuff, or hack on top of existing circuitry (like the 64MB memory expansion for my Atari 400...).

An AM transmitter (4, Interesting)

Announcer (816755) | more than 7 years ago | (#17080664)

It's designed for use on Amateur Radio frequencies, specifically between 3700-4000 Khz and uses basically the same technology as broadcast transmitters from the early days up to the 1960's.

Here's a Coral link to it: 46.htm []

The best part about it, is that I built it entirely from stuff that was headed to the scrap heap!

There are other interesting or unusual things I've built, which can be seen by following the links. In one especially unusual project, I used the analog circuits from a fried SoundBlaster card, and a CD drive as a modulator for a tube-based, low-power AM transmitter. Combining 2000's technology with 1950's. It worked, too!

Igloo (1)

owlnation (858981) | more than 7 years ago | (#17080666)

I built an Igloo once, that was really cool.


Re:Igloo (2, Insightful)

Bastard of Subhumani (827601) | more than 7 years ago | (#17080772)

I really did build an igloo! Three of us slept in it overnight. It was surprisingly comfortable.

Spaceballs:The FLAMETHROWER! (1)

heauxmeaux (869966) | more than 7 years ago | (#17080692)


In High School (2, Interesting)

nuclearpenguins (907128) | more than 7 years ago | (#17080700)

I built a 16' bong that utilized an electronic switch to open the chambers and 3 pc case fans to help propel the smoke. The bowl was an expensive tuba mouthpiece which held nearly an 8th of weed. I don't know if there are other former stoners here who would back up my claim that sometimes smoking leads to arts and crafts time.

Maybe not the coolest, but to me it was (0)

Anonymous Coward | more than 7 years ago | (#17080702)

I built a custom casket for my grandfather when he passed away. We both loved carpentry and I felt that it was my way of honouring a great man who taught me everything I know about something I love doing. To this day I still miss building stuff with him....

Cafeteria Inspiration (1)

eyefloater (659106) | more than 7 years ago | (#17080708)

I made a self supporting geodesic sphere out of french fry pick forks (the little two-prong ones).

Built, but never tested (2, Funny)

svunt (916464) | more than 7 years ago | (#17080728)

I once built a super-sweet ride, but I never got to really enjoy it, as it's prohibitively difficult to generate 1.8 jiggawatts of power.

Funnily enough, I'm in the process of... (1)

nowhere.elysium (924845) | more than 7 years ago | (#17080732)

...building something that I think is pretty cool.
Basically, I'm finishing off a degree in Digital Arts (went back to university after working for a few years), and my final piece is going to be an interactive VJ set, using a P5 virtual reality glove, an old QuickShot II joystick (harvested from one of my Commodore 64s), a Thinkpad 240X (lovely machine, that - perfect for coding at all hours of the day), and a couple of Mac minis (ideal rendering machines for this sort of thing...). I'm hoping to have it all ready for February: if any of you will be in London at the time, gimme a shout, and I'll send you directions to it :)

My best - the Abtaser (and my other IP flops, too) (4, Funny)

transporter_ii (986545) | more than 7 years ago | (#17080736)

Been working on a list of my biggest inventions and intellectual property items that flopped in a big, big way. My coolest inventions and IP flops are:

  • My book, "Men Are From Mars, and Women Love Martian Penis," failed to crack the NY Times Best Seller list for five consecutive years after publication.

  • NBC cancelled my sitcom, "Nudist, With Children," before a single episode was aired.

  • My idea for non-decomposing toilet paper never made it to market.

  • While at first very successful, my tubs of chocolate-chip cookie-dough flavored roach poison, designed to fool even the most intelligent roaches, were pulled from shelves nationwide. While a federal judge initially upheld an injunction on the recall, the injunction was later overturned by a law created in a special session of Congress (the law was named Kimberly's law, in honor of the memory of the two-year-old baby Kimberly).

But my all time coolest thing I have built, and my biggest tech flop, is one I called an abtaser:

Abtaser []

Because of their small size, AbTasers can fit easily in your purse, bag, backpack, coat etc. Other Ab products, like Ab belts, are bulky and only work your Abs. The AbTaser's design lets you not only work other parts of the body, but you can work other people's Abs from up to 15 feet away!

Conveniently carry it with you whenever traveling around town, shopping leaving bars or night clubs, using pay phones, parking lots, garages, alleys, subways, bus stations, home alone, walking, jogging, running errands, deliveries, and for house wives, students, daughters, night workers, drivers, law enforcers, sales people, travelers, security guards, etc., and for anyone needing or wanting extra exercise.

Other low-power Ab products have to be used for an extended period of time. The high-powered AbTaser works every muscle in your body in a split second. And again, not only is it capable of working your abs, but you can also work the muscles of others up to 15 feet away. Imagine your bosses surprise when you decide he needs a little exercise! AbTasers are great for relieving stress, too. Feeling down, feeling blue? AbTasers will give you a new outlook on life!

*Check federal, state and local laws before ordering your AbTaser! Do NOT carry your AbTaser concealed. Do not attempt to use the AbTaser while operating a motor vehicle. Do not use the AbTaser on someone else operating a motor vehicle. Do not attempt to board aircraft while in the possession of an AbTaser.

Automated Monorail (5, Interesting)

rongage (237813) | more than 7 years ago | (#17080740)

I think the coolest thing I ever built (or designed and programmed) was a self-contained turntable system for an automated monorail part transport system. The thing had multiple stop points that could be programmed, automatic homing, and built-in accel/decel ramping. Used a mini handheld pendant to program the stop points - you could literally walk under the thing and see the alignment as you made your adjustments.

To the best of my knowledge, it is still in production at Caterpillar today. It was designed and built in 1998.

The second best coolest thing I ever built was some software for interfacing a Linux based PC to an Allen Bradley ControlLogix PLC. The real cool bit is knowing that this software is being used in multiple production facilities around the world from making baby formula in Canada to being used in a mix simulator for the AirBorne Laser program.

Owwww.. difficult one (1)

StarfishOne (756076) | more than 7 years ago | (#17080744)

Does my SecondLife inventory count? :P

Cheap supercar (3, Interesting)

Lumpy (12016) | more than 7 years ago | (#17080746)

Put a corvette LS5 engine in a pontiac fiero. I now have 1Hp at the wheels for every 6 pounds of car. I can put crotch rocket motorcycles to shame, and eat any "fast" car I get challenged by.
Cost me a total of $15,000.00US and a year tinkering. the car costs $350 a year to insure and takes everyone by suprise that tries to race that slow old 80's wannabe sportscar.

Biggest drawback? touchy to drive. if you sneeze while accelerating slowly you suddenly burn the tires hard, have the nose lifting off the ground and are starting to go sideways. It's dangerous for anyone that doesn't know how to drive insane levels of Hp to weight ratios.

Re:Cheap supercar (1)

tompaulco (629533) | more than 7 years ago | (#17080862)

I have a cheap supercar, too. An '88 Lotus Esprit (about $17k these days). Earlier this year, the transmission input shaft bearing destroyed itself, so I completely disassembled the engine, got a larger bearing, had a machine turn the crankshaft to accept the larger bearing. Got the flywheel polished, got all new gaskets, rings, bearings, new clutch plate, input shaft, and all kinds of other stuff. I cleaned everything up in a parts washer, and got it all back togethr, and it actually ran. I had some help from an SAE, but it felt good to actually be able to learn how the engine works, and how all the parts go together.

Kegerator (5, Interesting)

Kairos21 (674835) | more than 7 years ago | (#17080748)

I built a 2 tap Kegerator with a tile counter and a computer to weigh the kegs and tell how much beer is left in each keg. Check it out here [] I also installed a glass door to keep liquor cold with a black light.

several machines (2, Interesting)

ArsonSmith (13997) | more than 7 years ago | (#17080754)

About 2 years ago I decided to get into hobbie prop building. One of the first things I built was a vacuum-forming table out of some MDF an empty beer keg a bit of metal from Home depot and a home built heating element. []

I have used this thing to make several diffirent things from speaker boxes to Stormtrooper armor. It has been a blast. The latest project I have made has been a rotocast machine. Rotocast%20Machine/ []

I started by building the lego mock up at the bottom of that link then started aquaring the other parts. It has been used to make several diffirent things from replica guns to costume masks and helmets.

Re:several machines (1)

ArsonSmith (13997) | more than 7 years ago | (#17080816)

Wow I make a lot I forgot about some of these other things.

This came from an article in MAKE Magazine []

This I got the idea from slashdot back 5 or 6 years ago when the Mame cabinets were all the nerdy rage: []
The one with the Mame across the top was built from scratch.

This one is still in my garage and is on the back burner right now but needs to be completed: []

Please go easy on my little gallery box it's only a PII dual 233 with 128 megs of ram.

You guys are just building toys... (0)

Anonymous Coward | more than 7 years ago | (#17080756)

I build nations.

My 2nd computer "chair" (1)

mrbcs (737902) | more than 7 years ago | (#17080758)

Pretty low tech compared to some of the geniuses here..

I had a welding shop at the time and I took a front seat from an old Lincoln car and attached it to a steel frame. I made it swivel and all the other adjustments were already in the seat. I had the keyboard and mouse mounted right on the chair. The keyboard would flip up out of the way to get in and out. The computer was in a cabinet with the 17" monitor on top. It was by far the most comfortable thing I ever used. I have since made another one that looks better, but not near as comfortable. (left the original 2000 miles away.. no room in the truck)

Just about everyone that saw it thought it was pretty cool.

What I built (1)

quiberon2 (986274) | more than 7 years ago | (#17080768)

I built a Linux which runs as a Windows screensaver. You can get it here [] .

a windmill, 5 m rotor diameter (0)

Anonymous Coward | more than 7 years ago | (#17080774)

I designed and built a windmill:

the diary that shows you how it was done []

Linux from scratch (1)

owlman17 (871857) | more than 7 years ago | (#17080796)

Old-timers used to do this routinely, but for relative noobs like me, [] nothing beats the joy of rolling your own distro, boot-strapping the compiler, etc. I suppose, those old-timers still find joy in doing this.

Lego Mindstorms (1)

physicsnick (1031656) | more than 7 years ago | (#17080798)

My brother and I once built a machine out of the Lego Mindstorms robotics kit that could make peanut butter and jam sandwiches. We also built a rudimentary photocopier. It was pretty sweet.

A Human Powered Submarine. (2, Interesting)

slashkitty (21637) | more than 7 years ago | (#17080800)

Here is the international contest we entered into: []

Well, I didn't actually see the end of the project, but we got a lot of it done. It was an awesome design, carbon fiber shell, aluminum frame and cool prop.

A transaxle (0)

Anonymous Coward | more than 7 years ago | (#17080804)

Well, I rebuilt it in front of the sheriff's house in battle mountain on Nov. 3.

A couple of things... (5, Interesting)

Chairboy (88841) | more than 7 years ago | (#17080814)

I've built a few things I really liked:
1. Building an airplane (200+mph 4 seater version of a Burt Rutan design)
2. Flamethrowers (the response time of the Culver City police department to 40+ foot flame mushroom clouds is 5 minutes)
3. TankCams - I've explored the crawlspace under my house from the comfort of my living room via teleoperation.
4. A couple of neat costumes, this year I was written up on slashdot about my Aliens walking forklift costume.
5. An inertially coupled autopilot for R/C planes I built years ago as a cheap UAV so I could send a plane someplace, take pictures, then have it fly itself back, all without crashing.

There are lots of cool things to do out there, I'll be dead when I stop working on them. Instead of being a "remember that time back when I was held the football record at Polk High" thread, I hope this thread focusses not just on past accomplishments, but also mentions things people are still actively doing, otherwise it'll be terribly depressing.

Liquid Fuel Rocket Engine (1)

Spikeorama (724224) | more than 7 years ago | (#17080818)

I'm working on a regeneratively cooled LOX/Kerosene rocket engine [] .
When I was 15, I built a Z-80 computer from my own design. I entered it in the science fair but the judges thought it was a kit so it got disqualified. I guess I did too good of a job wire wrapping it. I'll never forget the experience of hand-entering the bytes for my "operating system" into the EPROM burner at the local computer store. Needless to say, it didn't work the first time...

I once built a Surround Decoder (1)

human spam filter (994463) | more than 7 years ago | (#17080820)

Before there was 5.1, 7.1 etc, there was Dolby Surround. I thought I could not or want not afford buying a Surround Decoder, so I built one together with a friend. Everything was made using discrete components, OpAmp's and so on. The craziest part was the audio delay for the rear channel. We built it using only 74-series TTL logic, no micro processor or DSP. You could even change the amount of delay by turning a potentiometer which was connected to a A/D converter, the output of the A/D converter was used to control the size of the ring buffer which stored the samples. The bad thing was that in the end it sounded not very good because it was only 8-Bit.. lol. It was a good project, it took us forever and we learned a lot. Today I would just take a DSP kit and code my surround decoder.. no need for soldering anymore.

Tunneling Scanning Electron Microscope (5, Interesting)

Hiigara (649950) | more than 7 years ago | (#17080822)

While I was a Junior/Senior at Everett High School, (Lansing, Michigan), I built a tunneling scanning electron microscope. We originally followed/used a kit from the University of Muenster in Germany that I had learned about from Slashdot. Unfortunately, the documentation sucked, the circuit board was etched incorrectly and there was a design error. Furthermore, the control software was written is visual basic and was nothing more then a toy.

With the help of a electrical engineering group at Michigan State University we overcame the problems and I decided to modify the original design to use GXSM, a powerful open source electron microscope software package that is Linux only. This required adding a sranger digital signal processing board and stepping up the input/output voltages for the piezo crystals. Amazingly, almost all the work was done by myself or fellow students, MSU only guided us in understanding the circuit diagrams, making small adjustments, fixing the errors in the plans and designing/building the stepping circuits for my modifications.

I have some really great memories, spending all day in the basement lab I had set up, eating pizza while skipping all my classes with permission from the principal, "accidentally" burning my long time enemy with the soldering iron, ripping a chunk of my finger off jumping a network wiring cage to connect the main computer to the internet.

Working with the electronics and science was very interesting, but the most valuable experience came from lobbying for the funding from local government, assembling a team of fellow students to work on the project and starting a Nanotechnology elective class to actually use the damn thing. Eventually, former State Senator Virg Bernero (now Mayor of Lansing, Michigan) convinced BioPort (the company that makes the Anthrax vaccine) to provide the majority of the funds.

The project eventually inspired local university and government leaders (I wouldn't stop bugging them ;)) to support accelerated Nanotechnology development and commercialization while also encouraging applied and basic research. Michigan State University and the surrounding universities are home to world class researchers and students working on Nanotechnology and Nano-Biotechnology. It has been decided that it is time the state began to leverage that asset to create a bright 21st century future for our citizens.

I'm 19 years old, and thanks to the Slashdot article "build your own electron microscope" I've actually become something I'm proud of. I've built a tunneling scanning electron microscope, lobbied for funding and government support, founded a Nanotechnology class at Everett High School with help from a amazing science teacher who now is inspiring the class to even greater things while developing a soon to be accredited curriculum, hired as a contract consultant by a company in silicon valley, been sent overseas, all expenses paid to a nanotube conference in Japan by the same company and I now work at M.S.U. as the only employee in a new Nanotechnology supporting office at the college of Engineering. (There is also some other stuff I'm not allowed to speak of.)

I've met very important people from NASA's JPL, IBM, Oxford, Harvard and founders/pioneers of Nanotechnology.

In my free time, I lobby for the creation of a Michigan Institute of Nanotechnology, which will become the center of Nanotechnology in the state, facilitating the cooperation of private industry, research, academia and government to create jobs, businesses, breakthroughs and secure a portion of the world economy for ourselves. It already has a extremely wide and powerful base of support.

Not bad for someone who graduated with a 2.5 GPA.

Pneumatic scat launcher (4, Interesting)

TofuDog (735357) | more than 7 years ago | (#17080824)

A couple of years ago I built an air cannon [] for the purpose of launching mountain lion scat at prey species, as part of my study of prey responses to cues of predation risk. My first test-firing of my dog's turd (using a foam coffee cup sabot) launched it's payload >200 m towards a house on the next street (I hid rather than verify the point of dookie impact). Imagine, if you will, the joy of recreating the primal thrill of monkeys hurling their excrement through the bars -all under the guise of science, of course. Alas, the seals in the sprinkler valves blew out after a dozen firings and I reverted to the low-tech slingshit to complete my experiment. Now if I would just finish writing the Ph.D. instead of posting to slashdot...

Beer in a blender (0)

Anonymous Coward | more than 7 years ago | (#17080846)

For years I have been trying to produce a decent imitation of Guinness. [] I could never get it right, especially the mouth feel. The choice before me was to give up or invest some serious money in special dispensing equipment. Unlike most beers which are pressurized with carbon dioxide, Guinness is pressurized with nitrogen through special nozzles (when it is served on tap at least).

I decided to throw a half bottle of my homebrew in the blender (a full bottle will overflow). It worked great, the taste and texture were pretty much bang on. Of course such beer has to be consumed immediately because the oxygen in the air will ruin it in a matter of hours.

Naturally, I wondered if I had found a panacea for all kinds of stout. Dragon stout went into the blender next. OMG it was awful. Bleah.

Anyway, I ran through my remaining stock of stout quickly so, after racking some wine this afternoon, I'll be starting my next batch with the happy knowledge that I will enjoy drinking it a lot.

I've also built hundreds of gadgets but they are unimportant when compared with being able to produce a decent Guinness substitute.

BTW, a great place to check out other people's projects is

Trebuchet or Crane (1)

GeneralAntilles (571325) | more than 7 years ago | (#17080850)

Either the 20' tall 2"x4" trebuchet that I built with some friends over the summer or the "crane" device we built out of 4" PVC (about 8' tall) to bring all the desks in the school up onto the roof of the gym for our senior prank. Trebuchet probably pulls out the win simply for the flaming, explosive tennis ball potential.
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