As long as I'm here, I should probably also mention The Chronicles of Amber by Roger Zelazny. The first series, particularly, are among my all-time favorite books; I can re-read them essentially without limit. There's another universe I've vaguely thought about writing fic for, although no bunny has ever quite broken through to that level. Also the Narnia books, the Outlander series by Diana Gabeldon, Charles de Lint's Newford series, and Guy Gavriel Kay generally. And the Wild Cards series for awhile, although I stopped reading those around Book 7. The first three are on my re-read pile, though. And I might pick up the new one coming out soon. Another author whose books I read and re-read is Olivia Goldsmith. I know, one of these things is not like the others. But they're like popcorn, or potato chips -- I pick them up, and before I know it I've eaten the entire book. The First Wives Club and Fashionably Late, particularly.
Also The Sandman comics, and Love and Rockets, and Strangers in Paradise (which I should probably have given up long ago, but I can't bring myself to stop. I still haven't read the final volume), and Finder by Carla Speed MacNeil, which is an independent comic that I wholeheartedly recommend to anyone who loves stories. More recently, I've started reading manga -- I devoured Death Note whole, and am following Fruits Basket and One Piece (in print; I am resisting the world of scanlations because I don't like reading comic pages on the computer, I find it really awkward).
I'm sure I could think of more if I pushed myself and browsed my bookshelves some more, but for the sake of sparing all your Friends pages I'll stop now.