Open Source Software Games
You have found the way to Games on Open Source Software:
FlightGear Flight Simulator - Open source flight simulator under GPL licence for Windows, Linux, Mac OS-X, FreeBSD, SUN/Solaris, and SGI/IRIX platforms.
Space Invaders OpenGL
Ani(mated)-Chess - an OpenGL front end for a CHESSTOOL such as gnuchess.
BillardGL - Free OpenGL billiard game for Windows and Linux with sources under GPL licence
The Blue Mango Quest - 3D arcade game written in C/C++ and using openGL. The goal is to extend the pacman-style gameplay. This game runs both on Linux and win32 platforms and is released under the GPL License.
Boson - A real-time Linux strategy game for two players for KDE (Open Source, GNU GPL)
BZFlag - Free multiplayer multiplatform 3D tank battle game. Irix, Linux, BSD, Windows, Mac OS X and SGI platfor
Cannon Smash - A free and open source 3D ping-pong game based on OpenGL. (GNU GPL)
CarWorld driving simulator - Small driving simulator/demo with open source code
Critical Mass - SDL/OpenGL space shoot'em up game
3D Mines - SGI MineSweeper game in OpenGL
Danger from the Deep - Danger from the deep (aka dangerdeep) is a Free / Open Source World War II German submarine simulation. [Linux / Windows] (C++)
Doom Legacy - Port of ID Software's classic Doom game with OpenGL
Doomsday - Win32/Linux source port of Doom, Heretic and Hexen with OpenGL and Direct3D support for graphics, and DirectX/A3D for 3D sound effects.
FooBillard - Free OpenGL billard game for linux
glChess - A 3D chess interface - An open source 3D chess interface. It uses OpenGL and GtkGLArea (from GTK+) for UNIX platform.
Glest - Free 3d real time strategy project
Kokak's Doom Page - DoomGL (OpenGL compatible port of Doom) and ZDoomGL (OpenGL port of ZDoom, an advanced Doom sourceport)
Marathon - Microsoft's own Open Source Initiative, using the GPL'ed Marathon 2 source code, called Aleph One.
OpenGL Games - An index of commercial, free, open source, and freeware OpenGL based games.
Possible Worlds - subwar / wing Commander - style openGL accelerated 3D game that runs both under Linux and Win 9x / NT / 2k.
PrBoom - A Doom engine that closely emulates the original game.
S3D Connector - Online game finder and ELO ladder ranking for Sea3D Windows based 3-dimensional Settlers software.
Tux Racer - An Open Source project in which the user takes the form of Tux (the Linux Mascot) and races downhill through alpine trails.
Tuxedo T. Penguin: A Quest for Herring. - A free and open source 3D game, that uses OpenGL, which is staring the famous penguin Tux from Linux. (GNU GPL)
The Ur-Quan Masters - Multi-platform port based on the now public-domain source-code of Star Control II.
Vega Strike - Describes space simulation in which players trade and bounty hunt. Includes features, forum, manual, and downloads of beta versions Help build the largest human-edited directory on the web.