Book Recommendations

Being home for the summer, I have lots of time to read. Lots. I have a slew of books on the way, mostly naval and maritime history, but I also want to get in some non-academic reading. I've already started the Discworld series (finally!) but what else should I read? Humor, sci-fi, fantasy, and historical fiction are my main interest, but I also like non-fiction as well. Point me in some good directions, oh literary friends!