RTS game with the theme of Strategy by Design
FlightGear Flight Simulator: free open-source multiplatform flight sim
A free transportation simulator game
A strategy game with a high fantasy theme
Colonize the New World.
Domination is a game that is a bit like the board game Risk
Arianne is an engine to develop multiplayer online games like Stendhal
Air traffic control tower and radar simulator (solo + multi-player)
Zoomable user interface (ZUI) with file manager, file viewers and more
Cooperative multiplayer graphical RPG and adventure game
Action RPG that's easy to mod
Convert PSID and RSID files into C64 executables
Program for tournament management.
Game engine supporting many 3D/2D formats and graphic effects
Cross-platform real-time strategy game (3D)
Full featured MUD server with all the trimmings.
A free 3d game for PC that does not limit the player. Fight,Build,Gain
open-source implementation of the "kropki" (aka "tochki") game