Open Source MMORPG Framework
Vivid3D is a C++ IDE/3D engine, with python scripting.
A free 3D game engine to create games and realtimes scenes for Windows
Spring is a free RTS engine developed for Windows, Linux and Mac OS X.
2D game engine for traditional platform games
Open Game Bootstrap
a game library to develop audio games
3D Game engine
C++ Framework for slot machine games
Kinect based controller.
A 3D, fully concurrent game engine
3D game engine for C and C++
Pear3DEngine is a modern and modular 3D development framework
easy programming language for 2d games
Delphi-like IDE for cross-platform game development
A DirectX based graphics/physics engine