Michael Perkins

A beautiful audio-reactive processing animation by Robert Hodgin:

Toxiclibs is an open source library of Java and Processing functions for computational design. The library contains functions for audio, color, geometry, math and physics. The following video is a collection of experiments and projects using the library.

toxiclibs showreel from postspectacular on Vimeo.

The following video was created by Jonathan Brandel using the Processing programming language. The overlayed animation appears to be reacting to motion in the video. Brandel describes it as "new type of interactive visualization combining computer vision and audio analysis." Click here for more awesome videos by Brandel.

Manny Tan's Wiggle is a fun little interactive animation programmed in Processing.  You can interact by moving your mouse or clicking in the animation space.  Click here to play.

 Metamorphosis from Glenn Marshall on Vimeo.