Vendetta Online is a multi-platform 3D space-combat MMO for Windows, Mac, Linux/32 and Linux/64. The game permits players to interact in a vast online galaxy; fighting, trading, and mining their way to success. A "twitch" type real-time combat model makes true player skill the deciding factor instead of character advancement. Massive capital-ship battles shake the foundations of the major nations at war, while others struggle to push back the encroachment of the AI "Hives". A no-strings free trial is available.
BZFlag is a 3D, multiplayer, tank battle zone, capture the flag game that pits players against each other in a networked environment. It runs on Windows 95/98/NT/2000, Linux, MacOS 10.x, Irix, Solaris, and others. An OpenGL accelerator is highly recommended, but it is playable with 3D in software.
0verkill is a client-server 2D deathmatch-like game in ASCII art. It supports free connecting/disconnecting during the game, and runs well on modem lines. Graphics are in 16-color ASCII art with elaborate hero animations. 0verkill features 4 different weapons, grenades, invisibility, and armor. The package also contains reaperbot clients, a simple graphics editor, and a level editor.
SuperTux is a side-scrolling platform game. The hero in this game is Tux the Penguin, the game's only reference to Linux. On the journey to rescue Penny, who has been kidnapped by evil Nolok, Tux faces 23 different kinds of bad guys while jumping and running through 101 beautifully-drawn levels. The soundtrack is available on last.fm and similar sites.
Atanks is a multi-platform Scorched Earth clone similar to the Worms series of games. Annihilate the other tanks to earn money, then spend it on bigger and better shields and weapons to wipe out the opposition. It features a wide array of weapons, AI players, destructible landscape, weather, parachutes, teleports and a wide range of other features.