Extremely simple joystick rumble / vibration library
A graphics engine + toolkit.
Open source network game service
A very small multi-platform game engine for creating desktop games.
A truly extensible cross-platform game engine
An open source skateboard games engine written in C# and .NET.
Pear3DEngine is a modern and modular 3D development framework
C++ Game programming Framework
Cross-platform reimplementation of AMOS BASIC (runtime)
Multi-Language Wrapper Collection for the Irrlicht Engine
AMOS BASIC reimplementation in Java
A framework for games with defense towers along a path.
also download updates from files section
Read and write PGN format and test moves for legality.
The Lambda-Engine is a cross platform game engine.