How I have only found out about the TED site through this thread, I have no idea. It's possibly the best thing on the internet.
Anyway, saw this earlier and was amazed. Not so much by the technology, but by the fact this guy just chose to give away this software free because he could see it's uses in underpriveliged areas. Presumably he could made a lot of money with this, no?
Johnny Lee Demos Wii Remote Hacks