AS3 Utilities library (Games Development Framework)
The Lambda-Engine is a cross platform game engine.
A cross-platform OpenGL based lightweight scenegraph library
Simple Point & Click Game
A DirectX based graphics/physics engine
Cross-platform 2D game engine
Game framework on top of Python, Panda3D and Twisted
AMOS BASIC reimplementation in Java
Tween for Torque
A cross platform 3d c++ game engine
Zap Engine
Basic real-time simulation engine in C++
DREAM is an Open Source GCS
C++ SDL/Box2d Programming
A DirectX 9 C++ game engine
A simple WinAPI game engine