Closures in C

GCC and Clang. The syntax is ugly, but hell, it's C. Oh, and this is Apple's work, bumping their total number of useful contributions to computing to a whopping 2 (3 if you count Squeak; much of its development was at Disney).

http://lists.cs.uiuc.edu/pipermail/cfe-dev/2008-August/002670.html

>>4
WebKit, maybe? Yeah, KDE did the groundwork, but Apple made it usable.