We read Replay by Ken Grimwood this month for bookclub, and it was a very interesting book.  There were a few good discussions about morality of some of the actions the characters take, the Eurocentricness of the book, the way the author used the characters by focusing on their love more than the outer world, and the way the characters chose to use their extra lives.  I think the idea is great, but the book could have been so much more.