- Frets on Fire - The player has to strike the correct colored squares at the appropriate time during the songs to produce sounds. The objective of this game inspired by Guitar Hero is to finish a song and score the biggest amount of points possible. (Python) [Cross-platform]
- Hawk Software - Developer of the open source HAWK game engine, and the OpenNL portable networking library for Windows.
- Libregamewiki - The encyclopedia of free (as in freedom) games with free content.
- Playing the Open Source Game - Shawn Hargreaves has several Open Source projects and interesting articles about the future of Open Source games.
- Hot Potato Online - This game is a fast paced arena sport where players try to explode the opposition using a short-fused potato bomb.
- Adonthell - A fantasy RPG game available for Linux, FreeBSD and BeOS. MacOS and Windows support will come soon.
- MUSoSu - A free software project for playing, solving, and generating Sudoku games. (Java) [OS Independent]
- Snip - Open-source Tetris implementation.
- GtkPool - 8-ball pool for Linux with customizable physics.
- The Genius - Chess engine including artificial intelligence, user interface and several features.
- CSPoker - CSPoker is a lightweight poker client/server. Client implementations in Java and Flash. XML-based API. (Java) [GPLv2]
- FreeDroid - Clone of the classic game "Paradroid". (C, Python) [MacOS, Windows 95/98/2000, Linux]
- Extreme Tux Racer - An OpenGL racing game featuring Tux, the Linux mascot. The goal of the game is to slide down a snow- and ice-covered mountain as quickly as possible.(C++,TCL) [Linux,MacOS X]
- Final Frontier Trader - 2D single player space strategy, combat, and trading game. (C++) [OS Independent]
- Kraptor - 2D shoot'em up made with Allegro. (C) [GNU/Linux, Windows, DOS]
- Groundfire - A 2D real-time multiplayer tank battling game. (C++) [Windows 9X/2000/XP, Linux]
- Fate - A massive multiplayer space trading and combat game for Linux. [GPL]
- Danger from the Deep - Danger from the deep (aka dangerdeep) is a Free / Open Source World War II German submarine simulation. [Linux / Windows] (C++)
- OpenLieroX - OpenLieroX is the open source clone of the famous Liero (the realtime Worms) game.
- jQuizShow - Free quiz game based on the "Who Wants to Be a Millionaire" game show. Add your own questions for classroom use or for fun. [Java, OS Independent, GPL]
- irrlamb - irrlamb is a 3D game that probably involves a lot of physics and frustrating gameplay. (C++) [Linux, Windows] [GPL2]
- Flight Gear Flight Simulator - The FlightGear flight simulator project is an open-source, multi-platform, cooperative flight simulator development project. Source code for the entire project is available. (OpenGL)[OS Independent]
- Holtz - Zertz and Dvonn board games - Holtz is a GPL implementation of the abstract strategy board games Zèrtz and Dvonn from the GIPF project. (C++) [Linux, Windows] [GPLv2]
- Open Game Source - A web magazine devoted to open source game development.
- Free Gamer - Open source games weblog and list.
- SecurePlay Open Source Development SDKs - Build games on Secureplay sourcecode libraries in Flash/Java C++. Create secure game transactions for multiplayer games (player management, state/event control, random events, secret events) Platform independent Encrypted pluggable communications.
- Daimonin - Free isometric real-time MMORPG. 2d/3d graphics, 3d sound effects, digital ambient music.
- Enigma - A puzzle game based on oxyd. Runs on Windows, OS X, and most open source operating systems. (C++) [GPL]
- Deliantra - Deliantra is a free software, multiplayer RPG and adventure game, much similar in style to nethack and moria. It is fully graphical and runs in realtime and set in a medieval environment. (GPL) [GNU/Linux,Mac OS X, Windows]
- Small Apps and Games - Small apps and games developments.
- Planet SolarWolf - An updated clone of SolarFox which was released in 1983 for Atari 2600. The objective is to get through 60 levels collecting space boxes.
- Spice Trade - Colonize Europe in this Java based, open source game. Live an adventure in the 12th century world.
- PvPGN - A bnetd based gaming network server emulation project that supports battle.net games. Includes a wiki, a list of live servers and a support forum.
- Driving and Racing (5)
- Browser Based (6)
- Shooter (5)
- Strategy (4)