Supposedly, J.K. Rowling has said that a clue for how the Harry Potter series will end is mentioned in the first chapter of the first book. I'm not sure whether or not this is actually true, but I must say it has caused me to re-read that chapter (and let's face it - the entire series) about a billion times. Every time I read it, I have a different idea as to what the clue might be. My latest theories are:
Chapter 1 is called "The Boy Who Lived". Coincidence?
On page 17 (the last paragraph in this chapter), the story reads, "A breeze ruffled the neat hedges of Privet Drive, which lay silent and tidy under the inky sky, the very last place you would expect astonishing things to happen." This leads me to believe (for now) that the final chapter of the final book will end where the first book began - back on Privet Drive. Something is up with Harry's Aunt Petunia. I can't forget the Howler that Dumbledore sent her. It seems like she's been hiding something throughout all of these books. Perhaps she isn't a Muggle after all. Could she possibly be what saves Harry from his fate? Every book goes back to Harry's life on Privet Drive. Since this final book isn't supposed to begin there, I have a feeling that even if the story doesn't end there, Harry will have to go back at some point.