Good stuff all
I can't believe nobodies mentioned it yet, kind of a pereneniel favorite for this kind of list.
Robert Persig's Zen and the Art of Motorcycle Maintanence
Great book, with some good stuff to say about thought and other great books and schools of thought.
Used as a text for some lower level philosophy classes, as fodder for tearing apart in the same level for profs with different veiws of the author. I like the heck out of it, good introduction to indepth philosophical reading and analysys of thought. Does it in a friendly way, understandably to someone who isn't used to it.
Jon