Paranormal is an extremely customizable (pseudo-programmable) audio
visualization library, based (conceptually) on Winamp's AVS plugin.
The goal of Paranormal is to be as flexible as possible by providing
a number of 'actuators' that perform various tasks involved in
generating an image. These actuators can then be combined to create
a nearly unlimited number of effects. These combinations can be
saved to a file to be brought back later.

WWW: http://paranormal.sourceforge.net/