MadMapper - The Mapping Software
TouchDesigner - TouchDesigner is a visual development platform that equips you with the tools you need to create stunning realtime projects and rich user experiences.
Resolume - Resolume is an application for live video performances.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.
QLab - QLab, Live show control for Mac OS X.
Processing - C++ and Java programming at the speed of thought.