I highly recommend Hyperion and The Fall of Hyperion by Dan Simmons. Extremely well written. The two follow-up Endymion books you can skip, though.
Also recommend The Forge of God and Eon by Greg Bear.
For something different and a bit more earthy, The Narrows by Alexander Irvine is interesting. The ending surprised and kind of confused me, but in a good way.
I'll also third the recommendations for Alastair Reynolds. I just finished reading his Zima Blue anthology. Very well done.
I second the Hyperion series recommendations - those two books hold such a wide variety of everything - scenes (that river that flowed from one _____ to another to another), stories (so diverse!), and characters (Colonel Kassad and that suit of his, the Shrike...!). I also second ANYthing by Greg Bear. I have to say that I still remember getting to this one scene towards the end of The Forge of God (if you've read it, you
know which scene I'm talking about) all those years ago, and almost literally reading it breathlessly. I totally had what he was describing in my mind's eye, and it was a sight to behold alright. Scary as hell, too.
It's one of those moments that you wish you could re-experience going through for the first time over and over again, like (for me, at least) watching The Matrix for the first time, seeing the Balrog on-screen, freaking out at "DIVE DIVE DIVE HIT YOUR BURNERS PILOTS!", or even watching the FS1 intro.
Add to the list:
If you like/tolerate fantasy, definitely look for George R. R. Martin's "A Song of Ice and Fire" series (A Game of Thrones, A Clash of Kings, A Storm of Swords, A Feast for Crows, and the other 3 books that have yet to be written). LotR-scale epic fantasy, yet somehow written in a sci-fi-like manner. TONS of characters, very well-developed lore, great writing... and MASSIVE books, too - averaging 900 pages or so. From the Wikipedia entry:
The books are known for complex characters, sudden and often violent plot twists, and intricate political intrigue. In a genre where magic usually takes center stage, this series has a reputation for its limited and subtle use of magic, employing it as an ambiguous and often sinister background force. Finally, the novels do not (presently) center around a climactic clash between "Good" and "Evil;" plot lines have revolved primarily around political infighting and civil war, with only one or two storyline arcs even suggesting the possibility of an external threat.
The novels are narrated from a very strict third person limited omniscient perspective, the chapters alternating between different point of view characters. Martin's treatment of his characters makes them extremely hard to classify: very few can be labeled as "good" or "evil". The author also has a reputation of not being afraid to kill any character, no matter how major.
If you like sci-fi, get ANY of the books by Timothy Zahn, whether they be the Thrawn Trilogy (Heir to the Empire, Dark Force Rising, The Last Command), or any of his other series' or standalone books. He is one of those authors who manages to come up with unique twists and angles in pretty much every book - not just in the storyline, but in the culture and what-have-you of the races he invents. Top-notch stuff. To get an idea of what I mean, either get the Conqueror's trilogy (Conqueror's Pride, Conqueror's Heritage, Conqueror's Legacy) or something like The Green and the Gray, Warhorse, or Manta's Gift. Simply superb.
Orson Scott Card and his Ender series is also enrapturing. Just thinking about the various things in those books makes me want to read them again, but I just finished them right before I got into Martin's Song of Ice and Fire at the beginning of the year.
I've also had highly recommended to me a couple of other authors and their series', but I haven't been able to collect all the books, and so I haven't read beyond the first book in each, but I'll pass the recommendation on nonetheless: the Honor Harrington series by David Weber, and the Culture novels by Iain M. Banks.
If you want some REALLY different reading, try out some of Harry Turtledove's alternate history books - quite a ride, those. I first read one when I was young, so young that it took me a while to realize that it was, in fact, alternate history. It was only when I got the the part about the unfallen Byzantine empire having invented fireworks (I knew China was responsible for fireworks in the real world) that I realized what I was reading.
Finally, a few Star Trek authors that I will pick up most any book of theirs: Peter David, author of the novel Vendetta (Borg meet the Planet Killer), probably the only book I've read 20 times, Gene DeWeese, author of Chain of Attack and The Final Nexus (GREAT pair of books), Diane Duane, who wrote My Enemy, My Ally (Best. Romulan. Book. Ever.) and Doctor's Orders (gotta love McCoy).
