@baal46 I love Sins too but u should check Gemini Wars. Indie and unfinished but with many many good ideas. Doesn't have multi player yet but when it finally arrives... it'll be awesome.
Anyway, I'm getting rebellion :)
There is no better space RTS or 4x game in existence. If you like 4x (GalCiv, MOO) or RTS (Homeworld), this game is essential, and you should go buy it right now.
@baal46 There is a FAR better option, it's entitled «Endless Space» a fantastic MOO style game... in fact what MOO should have been.