Athreshtunes
My first QC iTunes Visualizer. Put this composition in /Library/Compositions and it will be available as an iTunes visualizer. It just vortexes a pseudo-colored version of the album art, and changes aspects of it depending on the volume of the track.

Athresh Effect
This takes the old "adaptive thresholding" composition and turns it into an effect suitable for putting in /Library/Compositions for use in iChat.

Aura Effect
This is a version of the Aura composition that obeys the Image Filter protocol. Thus, if you put it in /Library/Compositions (or ~/Library/Compositions) on Leopard and re-start iChat, it will be available as an effect in Video->Show Video Effects.

Feature Tracker
This composition uses the two feature tracking plug-ins listed on the "Custom Plug-In" download page.