The Pure Data (short Pd) project on SourceForge unifies the extensions (or externals) written for the Pure Data Graphical Computer Music System written by Miller Puckette with contributions from many others.
Spectrum3d is a software for Linux that displays the harmonics of the sound in 3D, either in real-time or from a preloaded file. It is multitouch and compatible with JACK.
It uses OpenGL, SDL, Gstreamer, Gtk+ and (optionally) libjack.
pd-codelab is a collection of abstractions, patchs and scripts for the Pure Data software made by the French community, notably around the forum http://codelab.fr
VisualCube is a volumetric display out of 6*6*6 voxels, where each voxel get's represented by a 2-color LED. This project includes a bunch of tools used to control this peace of hardware, by taking advantage of the VisualCube library.
IOverflow aims to be a 3D shooter game with a visual style loosely based on the game "Rez". It features a 3D Landscape that responds to the (player selected) music actually playing. (will also work as a fancy 3D screensaver)
MusicWatcher is a perl based non-realtime music analysis and visualization system with complete example implementations. One example renders a 3d music driven animation in povray.
Cross platform 3D midi and audio visualization system. Features an advanced graphics rendering engine, with ogre3d, and a data driven plug-in architecture which allows for programmers and artist to modify and create new "visualization instruments".
The CPU RightMark suite is meant for objective measurement of performance of modern and future processors in different computational tasks such as numerical modeling of physical processes and solving of 3D graphic problems.