Just out March 15 of this year, Red Eclipse is free multiplayer FPS on the Cube 2 engine.
However in a rare twist, the developers are also planing on creating a single-player Campaign.
The team original broke/branched from the (now collapsed) project Blood Frontier, and made their own game.
I found this, FPS three days ago, have not played it and so can't judge its quality.
Judging only by the Screenshots, and Video, this is certainly a polished looking Game.
Systems: Windows, Linux/BSD and Mac OSX
Edited by Red Fortress, 24 April 2011 - 12:31 AM.