A.J. Jacobs is thirsty for knowledge. He's also looking for a book gimmick, and the meaning of life. The Know-It-All is the story of his quest to read the entire Encyclopedia Brittanica over the course of one year (or so).
I like the way the book is laid out; he divides chapters by letters of the alphabet, and subchapters by words and topics he learned about. Obviously, he doesn't touch on every word, but he packs a lot of learning and knowledge into the book, and how what he read in the Brittanica affected how he views his life. It's also a sort of diary of his relationship with his family members and his attempts - with his wife - to have a baby.
It's a humorous, quick read, and well worth the time. Jacobs is occasionally a bit smug, but it's such a part of his personality that it's easy to overlook.