I've read Lord of the Rings three times, and like Amanda I probably will read the Harry Potter books again at some point. I've also read Len Deighton's Game, Set and Match trilogy a couple of times. Sometimes a book is just "right" for you at a certain time in your life, but not at other times. For example, I first read Douglas Coupland's Generation X when I was in my twenties and absolutely loved it. Recently I read it again and while I still thought it was a good book, it just didn't light my fire in anything like the same way it did twenty years ago.