MegaGlest

MegaGlest is an entertaining free (freeware and free software) and open source cross-platform 3D real-time strategy (RTS) game, where you control the armies of one of seven different factions: Tech, Magic, Egypt, Indians, Norsemen, Persian or Romans.

The game is setup in one of 17 naturally looking settings, which -like the unit models- are crafted with great appreciation for detail. A lot of additional game data can be downloaded from within the game at no cost.