Odamex is a free, cross-platform, modern client-server Doom engine
0 A.D. is a free, open-source, cross-platform real-time strategy game.
Air traffic control tower and radar simulator (solo + multi-player)
Cross-platform real-time strategy game (3D)
A free 3d game for PC that does not limit the player. Fight,Build,Gain
Advanced map editor
A fun realistic multiplayer free-and-open-source first-person-shooter!
Free MMORPG
3D Space Station Simulator (inspired by SS13)
A java desktop game to play tic tac toe in a new way on a 3X3X3 cube!!
Free 3D Roguelike action RPG
3D FPS Digital Paintball 3 Multiplayer Online Game
The original Xivio.com World Server Core
Minecraft private Skin Center
Action-packed local multiplayer game
A Dungeons & Dragons Miniature Game.
A multiplayer First-Person-Shooter game built in Java 3D