Also, I don't think anyone has mentioned Greg Egan yet. If you like hard SF and/or 'cyberpunk' type stories, he will blow your face off.
I'd recommend Axiomatic, Quarantine, or Luminous.
And Greg Bear is great... he goes from heavy SF, goes into Stephen King territory, has some fantasy-type stuff... it's super. If you ever read Hegira... you don't really know what 'type' of book you're reading until it's almost over
...And if you like things like Star Wars... and space-fantasy garbage type stuff... I've recently been sucked into reading Warhammer books, starting with the Gaunt's Ghosts series. The whole Warhammer universe is a big mashup of every other major science fiction property, like Dune, the Foundation books, Star Wars, Starship Troopers, the stories of HP Lovecraft, Aliens, and whatnot. Gaunt's Ghosts is World War 2 in space against evil posessed cults. The Horus Heresy books are also kind of fun to read so far.