Thousand Parsec is a framework for turn based 4 X's game (eXplore, eXpand, eXploit, eXterminate). Designed for long games, supporting massive universes and has an easily expanded tech tree. Platforms: Windows, BSD, Mac, Linux

A city simulation strategy, like the famous SimCity. Platforms: BSD, Mac, Linux

XLattice is a communications infrastructure for server-assisted peer-to-peer networks.Initial implementation is Java (and so platform-independent) with C/C++ for Linux and then Windows to follow. Platforms: Windows, Mac, Linux

PyBEM is a simple project: Python. Play by Email. That's it :) We're providing tools to help people create and run their own turn-based strategy games via email, in a language that's simple to learn, and using a system that's easy to modify. Platforms: Windows, Mac, Linux

Ng is a 100% Java Roguelike game engine that supports single and massive multiplayer games. SimpleGame is a prototype game that demonstrates most features of the engine and is included in all releases of Ng. Platforms: Windows, Mac, Solaris, Linux

TNF2 is based loosely on the original game TNF (The New Frontiers) http://www.geocities.com/TimesSquare/Castle/2979/ written and designed by Jerry Revell Jerry@starchase.demon.co.uk. Simply put the game is about space colonization. Each player runs a Platforms: Windows, Mac, Linux

The Java VGA-Planets Client is a Java based client for the Play-by-Email game VGA-Planets. Platforms: Windows, Mac, Linux

a multi-player game, similar to worms, gunbound and scorched earth, played in real time. Written in C++ using SDL Libraries. Platforms: Windows, BSD, Mac, Linux

The Asian game of Go takes place two-dimensional board. Its idea readily extends to three dimensions - placing stones on a cubic grid. This is a program for playing on such a three-dimensional grid. It runs under Java and needs the Java3D extension. Platforms: BSD, Windows, Mac, Linux

The EDF Project is an attempt to create a vaguely X-Com like game, but with many new features (including real multiplayer) and a _completely_ different plot, although still involving aliens. Platforms: Windows, BSD, Mac, Linux

The Cyber Hordes is a single or multi-player RTS game where each player builds robots and gives them various components (weapons etc..) and then general orders (e.g. Attack), which the AI of the robot will attempt to complete on its own. Platforms: Windows, Mac, Linux

A strategic turn-based game, based on Battle of Wesnoth engine, to make to live again the ancient Glory of the Celts, where the respect for the nature and the observance of the mystic was stirred in the life every day. Platforms: Windows, Mac, Linux

The BUG Mod (Beyond the Sword Unaltered Gameplay) is a mod for the popular TBS game Civilization IV: Beyond the Sword. This mod adds many interface enhancements that aid game play without modifying the rules or providing hidden information. Platforms: Windows, Mac, Linux

Battleship game written in Java.Network support (dedicated server).(needs at least JRE1.4) Platforms: Windows, Mac, Linux

This project is a massively multiplayer online game played through your webbrowser. You control a ship and planet in the startrek universe and carve out an existance with other players, eventually it is possible to create your own fleet and empire. Platforms: Windows, Mac, Linux

Terminal Delusion is a project to build a game that will be fun to play, have a good storyline, humour, music and atmosphere. Possibly not very good graphics at first. And it will be written in Python. Plus: all content and tools under an open license. Platforms: Windows, Mac, Linux

Tenes Empanadas Graciela (TEG) is a clone of 'Plan Tactico y Estrategico de la Guerra', which is a pseudo-clone of Risk, a multiplayer turn-based strategy game. Platforms: BSD, Mac, Linux

TempusPre is a free, persistent online strategy game. Choose your race and start building, developing and fight to extend your kingdom. (development on the open source branch has stopped, only the proprietary branch is developed further) Platforms: Windows, Mac, Linux

Temple Tycoon is a Real Time Strategy Game with the purpose to convert people's religion to the 'Euphemisms'. Be sure to build enough Coffee Shops, Farms, Fields and Temples though. Check it out! Platforms: Windows, BSD, Mac

A web-based game in the spirit of Archmage of a post-apocalyptic future. A jsp-based MMORPG where users control empires spanning many worlds. Writers and artists welcome. Employing Struts MVC, Tomcat, mySQL, and Java. Knowledge of design patterns helpful Platforms: Windows, Mac, Linux