Java decentralized cross-platform network multiplayer game engine
Gorgon Game Engine (GGE) is a C++ game engine that handles many tasks.
a game library to develop audio games
Java Gamepad API for multiple platforms
Multi-threaded 2D Renderer licensed under the Mozilla Public License
A multiplatform game engine for interactive fiction experiences
Pear3DEngine is a modern and modular 3D development framework
Open Source Virtual World and MMOG Development Platform
DiaT is a Textadventure
Framework for a graphical point and click adventure game in Java
AMOS BASIC reimplementation in Java
A DirectX based graphics/physics engine