For those playing 4x strategy games, this is one for you : Galactic Civilizations.
It’s so good that I have to advertise it!!
Strong points are:
•    Very good AI !! And it doesn’t cheat, it just kick your ass!
•    Interface easy to use and intuitive.
•    Different victory conditions for different strategies
•    A sort of roleplaying between Good and Evil
And of course all the things that make a 4x game.
It reminds me a lot of SMAC in its presentation.
Cons would be:
•    No ship design
•    No tactical combat ( but a combat ‘a la civ’)
•    No choice of civilization (but a lot of customization)
•    No multiplayer
To make your own opinion and know about the game, the developperand the philosophy behind:
•   ÂÂ
www.galciv.com , the official website where you can buy (and download!) the game.
•   ÂÂ
apolyton.net/galciv/ , at Apolyton, there are links to all reviews, screenshots, etc..
Good game!