Fellows, a personal favourite from a while back has been iterated upon and upgraded to a fine, fine experience. If you're in the mood for an arcade-style 4X space strategy that takes equal cues from Masters of Orion 2 and Galcon, do yourself a favour and investigate
Distant Star. It was an enjoyable, if bare-boned game upon launch, but now it's got a ton of new features...tightened tech tree, planetary development, upgrading etc.
There's a lot of tongue-in-cheek sci-fi geekery love to be found within. It's a fast-paced game that is tactically sound and very easy on the eye with its delicious minimalist pixel aesthetic.
Highly recommended. All it needs is a little asynch love, but it moves at such a high pace that you'd lose a lot of the momentum if it required someone on the other end to log in and do a single move. As it stands, a great little single player slice of goodness. Would make for great bluetooth local multiplayer, though.