Vvvv - vvvv is a graphical programming environment for easy prototyping and development.
Unity - The multiplatform game creation tools for everyone.
Processing - C++ and Java programming at the speed of thought.
Godot Engine - Feature-packed 2D and 3D open source game engine.
Vuo - Design and build live interactive media.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.