Samba 4.0 Released: the First Free Software Active Directory Compatible Server
Somebody announces something awesome, and the actual developers show up in the comment thread further enhancing the awesome, and now I have to go download some stuff and try things out just for the hell of it.
It's like Slashdot Circa 1998. Crazy.
Hey you kids! Git offen mah lawn!
The Importance of OS Backwards Compatibility
Backward Compatibility: Running your COBOL written in 1971 on the current release of z/OS without changes.
FYI: the hardware architecture has gone through 2 addressing mode changes since then - from 24, to 31, and now 64 bit addressing.