vrmlguy's Journal: Needed: a Bluetooth-enabled chair cushion

In an effort to encourage people to lock their workstations, my place of work has decided that anyone leaving their system unlocked will send out an email volunteering to buy donuts the next day. Of course, the poor saps usually don't realize that they've sent that email until they start getting replies thanking them. I've decided that it would be cheaper for me to purchase (or build) a seat cushion that reports to my laptop if my butt is resting upon it, and have an app that activates the screen saver whenever I stand up. While this seems like a natural for ThinkGeek, I can't find anything like this in their catalog (although the BluAlert bracelet looks interesting). And I don't need something expensive that measures my exact weight. Can anyone please help?