Links

Nexuiz - another popular multiplayer FPS game, has some small relation to OpenArena

OpenQuartz, one of the first Free Data projects for a GPL'd FPS engine.

FreeDOOM, Free Data project for the GPL'd Doom sources. Modified BSD license.

Blasphemer, Free Data project for GPL'D Heretic sources.

FreeGameArts, probably one of the only truly Free resources of media to exist!

Linux Game Tome, news about games for linux.

Related productions:
(If you like OpenArena you'll like these. These are also GNU GPL but they are also in early development)

OQPlus - a fork of OpenQuartz that has a differing creative direction (centered weapons, no zombie trees)
Haktoria - an anime-styled open source fantasy FPS/RPG game
XDFort - an anime-styled open source team-based FPS game
Fired Guns - Open Source classic style "lots of cool guns" mod for Quakeworld/OQ/OQPlus

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