Ganked from phoenixalpha.
1. The Lord of the Rings*, J.R.R. Tolkien
2. The Foundation Trilogy, Isaac Asimov
3. Dune, Frank Herbert
This is one of four Heinlein novels I really don't like. One of the others was written at about the same time, and the other two much later in his dotage.
5. A Wizard of Earthsea, Ursula K. Le Guin
6. Neuromancer**, William Gibson
The movie was better.
9. The Mists of Avalon, Marion Zimmer Bradley
I think you could make a better case for the Darkover novels, myself.
10. Fahrenheit 451, Ray Bradbury
11. The Book of the New Sun, Gene Wolfe
12. A Canticle for Leibowitz, Walter M. Miller, Jr.
13. The Caves of Steel, Isaac Asimov
14. Children of the Atom, Wilmar Shiras
Heh. Now this is obscure...I read the original printing in Astounding SF.
15. Cities in Flight**, James Blish
16. The Colour of Magic, Terry Pratchett
17. Dangerous Visions, edited by Harlan Ellison
A hundred years from now, people are going to regard him as the William Burroughs of science fiction, and no, that's not a compliment.
19. The Demolished Man, Alfred Bester
20. Dhalgren, Samuel R. Delany
Can you say "unreadable poser"? I knew that you could.
21. Dragonflight, Anne McCaffrey
22. Ender's Game***, Orson Scott Card
One of the few stories I know that was improved by becoming a novel - and the original story was pretty goddamn good.
23. The First Chronicles of Thomas Covenant the Unbeliever, Stephen R. Donaldson
24. The Forever War*, Joe Haldeman
I remember all the fuss when the parts of this started coming out in ASF. "OMGWTFBBQ! Soldiers having SEX!!! IN ANALOG!!!!111!!oneoneone111!!!!"
25. Gateway, Frederik Pohl
26. Harry Potter and the Philosopher's Stone, J.K. Rowling
27. The Hitchhiker's Guide to the Galaxy, Douglas Adams
28. I Am Legend, Richard Matheson
Here again, the movie (The Omega Man) was better.
29. Interview with the Vampire, Anne Rice
30. The Left Hand of Darkness, Ursula K. Le Guin
31. Little, Big, John Crowley
32. Lord of Light,* Roger Zelazny
33. The Man in the High Castle, Philip K. Dick
Not actually his best work, but the one everyone remembers.
34. Mission of Gravity, Hal Clement
35. More Than Human, Theodore Sturgeon
36. The Rediscovery of Man, Cordwainer Smith
You know, I think I may not have actually read this, but what else is there besides Norstrilia and The Instrumentality of Man?
Depressing, but not as much so as the movie.
39. Ringworld*, Larry Niven
40. Rogue Moon, Algis Budrys
41. The Silmarillion, J.R.R. Tolkien
42. Slaughterhouse-5, Kurt Vonnegut
43. Snow Crash**, Neal Stephenson
44. Stand on Zanzibar, John Brunner
45. The Stars My Destination***, Alfred Bester
This badly needs to be done as a Bruce Willis movie. What's that guy who did The Fifth Element doing these days?
46. Starship Troopers**, Robert A. Heinlein
47. Stormbringer, Michael Moorcock
Elric. Daaarling. ^____^
48. The Sword of Shannara, Terry Brooks
49. Timescape, Gregory Benford
50. To Your Scattered Bodies Go*, Philip Jose Farmer