Shutter Island. Good book, fast read. Gripping storyline, overall good pace, and an interesting (read:crazy) end. I finished it in a couple of nights. Recommended to me by my good friend Anand (who reviews movies here).
The book is being turned into a movie starring Leonardo DiCaprio and is being directed by Martin Scorsese. Scheduled for early 2010, the trailers are already out. Check it out.