MilkDrop - 3D audio visualization plugin, compatible with WinAmp plugin API
Saber - Quick and Easy Website Feedback - Stop losing customers to website errors and usability problems. Get Saber's website feedback tool for quality user feedback, suggestions and bug reports.
projectM - projectM is an LGPL'ed reimplementation of Milkdrop under OpenGL.
Butter Churn viz - WebGL implementation of the Milkdrop 2 visualizer
Magic Music Visuals - Fully-customizable and highly responsive visuals for live and recorded audio & MIDI.
SWORD - SWORD is a windows software tool for managing a field service company.