Open-source, cross-platform, game-development tools
Easy fine console input/output for java
486 lines of C++: old-school FPS in a weekend
scriptable game engine with built-in support for 2D graphics and sound
Highly customizable library for procedural world generation
Realtime 3D engine for game development
Highly portable Gameboy Color emulator
2D game creation software
Cross-platform C framework very compact libraries and tools.
C++ Framework for slot machine games
Cross platform 2D game creation framework with Python bindings
Simple C++ library for path manipulation
Investigo - DX9 Performance and Debugging Toolkit
easy programming language for 2d games