Arianne is an engine to develop multiplayer online games like Stendhal
X3D Prototypes for the SMUOS Component
Event driven concurrent framework for Python
3D .NET engine for Windows, Linux, Mac
Single-/multi-player card game Mau Mau (similar to UNO®)
evolution for vegastrike SpaceSim/Combat/Trade game
Java decentralized cross-platform network multiplayer game engine
c# lua bind with unity3d project for game development
Free strategy browsergame engine.
Gives agents personality, moods, emotions and emotional attachments.
A 2D Adventure Game & Engine
Modular Gaming Open Source Persistent Browser Based Game Framework
Library for creating turn-based games with simultaneous moves.
TR Game Engine allows you to develop your game quickly and easily.
Open source network game service
An extensible development framework for roleplay games.