Wildfire Games announced the release of 0 A.D. this morning. "This release comes with aggressive units that attack enemies on sight, lifelike animals that escape danger, two new maps, in-game multi-player chat and much more." This open-source 3D game is available for Linux, Windows, and Mac OS X operating systems.
As mentioned in the release announcement, there's quite a few changes to be found in this newest development snapshot, but there's still room for many more improvements. There is a video below that's provided by Wildfire Games for those that have not yet tried out 0 A.D.
It's been a good month so far for those interested in open-source / Linux gaming with id Software opening up Enemy Territory and Return To Castle Wolfenstein, And Yet It Moves being released for Linux, Amnesia coming soon, Rigs of Rods getting a release, and best of all there's an imminent announcement from the developers of the Unigine Engine.