I read Starhammer by Christopher Rowley. That was interesting, and quite a bit cheesey.

Someone was just at my desk and I recommended Eric Nylund's Halo books to them. I don't see why I shouldn't do the same to you. ;)

And, maybe a slight breach in protocol here, but the Annihilation books in Marvel Comic's series are really good. There are 5 HC/TPBs that you can get the first two series in. After that, it gets more complicated.

Likewise, I just read Geoff John's Green Lantern Rebirth and Sinestro Corps War. Those were alright. I'm not a DC guy, and I found these 3 TPBs to be mostly self contained.