Curiously, two novels titled The Cloud Atlas were published within a few months in 2005. While I recommend both, I really, really liked the one by David Mitchell.
Cloud Atlas consists of eleven stories, the eleventh being the second half of the first, the tenth being the second half of the second, and so on. Each of the first six stories takes place in a different era, moving forward in time from the 19th century to the far future. Each is written in a different style, and each incorporates elements from the preceeding stories. The stories themselves are mind-benders, as well.
A sucker for this kind of structural razzle-dazzle myself, I know it leaves many people cold, especially when it comes at the expense of characterization, which, to be fair, it often does. For those folks, let me recommend Mitchell’s next novel, Black Swan Green, which goes deep into its narrator’s character, a teen growing up in Thatcher’s England.