Nonfiction: Lots - from periodicals to online to books. My favorite authors: John McPhee who writes about anything and makes it interesting, Bernd Heinrich, best known about his works about ravens, and Edwin Way Teale, mid 20th century naturalist
Realistic Fiction : John McDonald's Travis McGee series, Tony Hillerman's Chee/Leaphorn series about the 4 Corners area of the US, many others
Historical Fiction: Patrick O'Brian's Aubrey/Maturin series about early 19th century British navy exploits
Fantasy: Tolkien
Science Fiction: Larry Niven, Arthur C Clarke, Heinlein, Frank Herbert and a host of others over the years
Horror : not much, but a few Stephen King
Comix : I have the twenty pound compendiums of Calvin and Hobbes and The Far Side - always a great reference.
Popular Science: Carl Sagan, Stephen Jay Gould, Jared Diamond command the most bookshelf space.
Many nature guides covering all natural sciences.
...And then there's the web, which takes too much time away from by book larnin' The latest wrinkle in this addiction is something called Hypography Science Forums.
