I really liked Bruce Sterling's Schismatrix when I read it in high school. It's set in Sterling's Shaper/Mechanist universe, where humanity is expanding into the solar system and modifying itself with cybernetics and biological engineering, slowly evolving into something posthuman. Sterling's Holy Fire was a bit more down-to-earth later transhuman novel I also liked.
I have never read very much Science Fiction, unlike some of the people here on Less Wrong, and I think I would like to. At least, the few books I have read I enjoyed. I've read a couple of books from Asimov's Foundation Series, two Michael Crichton books, Twenty Thousand Leagues Under the Sea by Jules Verne, and an anthology of SciFi short stories (no really famous authors) that my dad owned.
That list looks very short. I just finished reading a fiction book, and am looking to start another. Recommendations? What are the two or three books I simply must read?