For those of you into the whole possession thing, there's an extremely disturbing article here about the real "Emily Rose," who was actually a German girl named Anneliese Michel.  The story is so deeply horrifying that I almost found it a relief to read that, as part of her possession, Anneliese "compulsively performed up to 400 squats a day." Whatever was torturing the poor girl apparently also wanted to keep her fit. I wonder if that part's in the movie.

[Thanks to Fat Wallet]