Microsoft has donated Allegiance to the Open Source community. Allegiance was given an award for "Best Game No One Played". Due to initial implementation problems, the game flopped, even though it was one of the most advanced team-based Space Sim Games out there.

You can get the source code for the game directly from Microsoft at http://research.microsoft.com/research/allegiance/

Get in with the Allegiance Community at www.freeallegiance.org