I love the LoTR Trilogy by JRR Tolkien, "The Hitchhiker's Guide to the Galaxy" by Douglas Adams, "Soul Music" by Terry Pratchett, and "Magic's Pawn" by Mercedes Lackey. I also love "Beowulf", but that's not really a book.
His Dark Materials Trilogy - Phillip Pullman
The House of the Scorpion - Nancy Farmer
The Da Vinci Code - Dan Brown
Cat's Cradle - Kurt Vonnegut (He never fails to amuse me)
The Giver - Lois Lowry
Harry Potter is also good, but slightly too popular to go on my favorite's list. These are books I recommend to others, and Harry Potter is one of those books *everybody* knows about, and nobody needs to hear me telling them to go read them! xd