I can't see this posted here yet so apologises if I'm wrong. The guy has been playing around with the infared technology that comes with the Wii and has done some completely amazing things with it. It's best just to watch the videos so you can see for yourself. The best is left till last and I'm truly of the opinion this could actually revolutionise how we play games as much as the Wii console itself. Still save it till last and watch your gob hit the floor
Johnny Chung Lee - Projects - Wii
Thanks to OneOne @ DearWandy forums for the link