In reply to Frank4short:
Not sure if these are what you're looking for but as I rate and enjoyed the ones that you mentioned, I'll toss them into the pile...
The Sparrow by Mary Doria Russell - Jesuits travel to another planet 'so they might better know God's other children'. Brilliantly structured, a real page turner, full of well realised and complex characters, it deals with religion and cultural misconceptions in a profound way, a stunning book that won loads of awards.
Neal Stephenson's books...
Snow Crash is pure cyberpunk fun. Diamond Age is more thoughtful, Anathem is long, meaty and you need to stick with it for about 150 pages until you can get your head around what he's doing, but after that - wowser. A unique mix of action, huge stakes and long philosophical discussions. Plus some very weird stuff at the end. Very entertaining book by a very clever guy.
China Mieville - Embassytown - Definitely at the cereberal/high concept end of the market. If you can follow all of this on first reading you're a better man than I, but he's (for my money) the best genre writer around. It's about language and linguistic concepts - Speilberg will not be filming this!. Some of his books are more enjoyable than others but I can't imagine anyone else even attempting a lot of what he does.