On Wednesdays I put up WAYR and I just list what I am reading now, with some notes; then you do the same in the comments. It's fun, and many of us learn about great books.
But I also like my special editions, and I haven't posted one in a while.
So .... on occasional Sunday mornings I will post special editions.
Last time, I had a poll and History/Historical Biography tied with Science Fiction. But, looking over my shelves, I realize that I don't have all that many history books - I am not sure where they got to. So, SF it is
I've been reading SF for a long time. I'm 51 years old, and I'd say I've been reading SF for at least 40 of them.
My first forays into SF were with the 'Big 3' - Heinlein, Asimov, and Clarke. Re-reading them now, I am amazed at Heinlein's politics (bad) and storytelling ability (good), and at Asimov's poor writing but excellent ideas. Clarke gives me less strong feeling.
Nowadays, I have different favorites.
John Varley. Varley writes amazingly well, he has interesting ideas. He likes to surprise the reader, not by smacking you in the head when you least expect it, but in more subtle ways. Persistence of Vision, for example, is a short story about a post-apocalyptic world, and it's a lovely, gentle, moving piece. Press Enter, is a short story about the near future, and it is as scary as anything. Many of his novels are set in a world where mankind has been wiped out on Earth, and survives only in the rest of the solar system, but in none of those novels is that the main theme (any more than the bubonic plagues features heavily in regular literature). He also likes to mess about with sexual roles.
Neal Stephenson. Some of what Stephenson writes is SF and no question about it. Snow Crash, and The Diamond Age, are SF novels. Other of his work is more ambiguously SF. I love Cryptonomicon, and it's hard to say that this is really SF, but it feels like SF. The Baroque Cycle is more clearly not SF, but still involves a lot of things that SF often does. And Anathem may not even be a novel; it's more like the memoirs or autobiography of a man who lives in a different universe.
Terry Pratchett. Discworld! His early books are good, some are very good indeed. Small Gods is a hysterical send-up of religion and fanaticism. But they get better. He takes on big social issues, and stays funny. Monstrous Regiment takes on sexism and the military. Thud! takes on racism and bigotry (as does Jingo). In The Truth a free press comes to AnkhMorpork, and it's hungry! And his latest Unseen Academicals takes on academia and sport fanatics. (By the way, the Discworld, shaped like disk, floats through the universe on the back of four big elephants, who stand on a giant turtle).
Theodore Sturgeon. More classically SF, but very good writing. More than Human is an amazing book, that packs a huge wallop into one line. Sturgeon mostly writes short stories.
Connie Willis is very funny indeed, I especially like Bellwether.
Max Barry wrote the wonderful Jennifer Government which is a little less scary now that Bush is out of office.
Walter M. Miller wrote A Canticle for Leibowitz which is one of the best post-apocalypse novels ever. Monks have preserved what knowledge they can, devotedly copying things they don't really understand, including a shopping list from the Blessed Saint Leibowitz.
If you like things weird, in a 60s sort of way, then Philip K. Dick is highly recommended, and if you like them weird in a way that's all its own, Cordwainer Smith is excellent. (Very hard to describe either author).
David Brin has written a lot of good books, especially Earth and The Postman , plus, he's a kossack!
Samuel Delaney is interesting. I found his magnum opus Dhalgren unreadable, but a lot of his other work is great. I especially like Babel-17 and Trouble on Triton
Harlan Ellison writes angry books, with a voice that sounds like it comes from the 1960s (and some of his writing is from then Dangerous Visions was written in 1967).
William Gibson and Bruce Sterling are stars of cyberpunk; both are very good writers.