Note: this post is from 2007, outbound links may be broken.
Wii Loop Machine – sync, control, and manipulate loops in real time
The Wii Loop Machine is a system for using the wireless Wii remote to sync, control, and manipulate loops in real time.
Check this video to see what that means.
The software is created with Max/MSP and runs as stand-alone software on Mac OSX (10.4.8 or 10.4.9 recommended).
Check The Amazing Rolo for more information and a link to download the Wii Loop Machine for Mac OSX.