Here's another processing project created by myself and Jim Taylor, another first year MFA. You drag the mouse around the screen and it paints a sandy landscape colored by the sounds of the music.
To run this file, you need two libraries, the Minim audio library:
http://code.compartmental.net/tools/minim/
and the physics library:
http://www.cs.princeton.edu/%7Etraer/physics/
Also, you'll need to put an mp3 file in the same directory as the processing project and replace "missyou.mp3" with the appropriate song filename. I can't upload missyou.mp3 due to copyright purposes : ].
Enjoy!
-Sean