In reply to climbingpixie:
Peter F Hamilton's two Commonwealth books are good - they preceded the Void trilogy (by some centuries). Fallen Dragon is a stand alone story which I think may be his best work.
I don't think his Void series is a patch on the Night's Dawn. Night's Dawn at least had loads of interesting imaginative things all the way up to the end. The Void series is (being unkind) a below-par fantasy story interleaved with a boring by-the-numbers futuristic action adventure, all with an equally deus-ex-machina ending. I read it to the end, hoping that something interesting would turn up, but I don't think I'll read another Hamilton series again.
On the good side:
Hannu Rajaniemi's The Quantum Thief. High tech, great concepts, loads of action.
Neal Stephenson. I've read Snow Crash and The Diamond Age. Good stuff.
I'll echo Dan Simmons' Hyperion and Endymion series - they're simply fantastic; Illium is also good. They're not Hard Science Fiction, though.