Comment Glest, for some open source RTS goodness (Score 1) 634
Put Glest on there as well ( http://www.glest.org/ ) Very polished looking RTS. From their website " Glest is a free 3D real-time strategy game, where you control the armies of two different factions: Tech, which is mainly composed of warriors and mechanical devices, and Magic, that prefers mages and summoned creatures in the battlefield. "
It is available from Ubuntu repositories.