Sometimes I wish I could be like some of the other great bloggers that I follow and read really "deep" books, but honestly - I prefer a good novel over most anything else.
Erik Larson writes nonfiction as if it was fiction. I get totally caught up in the real-life characters, and have to restrain myself from Wikipedia-ing the actual events so I don't spoil the rest of the book. The Devil in the White City focuses on the story of how the amazing Chicago's World Fair came about and ties it to America's first real documented serial killer, Dr. H. H. Holmes (and man, oh man - he makes Ted Bundy look like a pansy). I was hooked from the first chapter.