I've never reread a book, but I do watch movies over and over again. I think that's because movies have so much going on that you have to narrow your focus one element and when you watch it again, you always notice new things happening in the background or a line of dialogue you missed the first time around. Whereas, with a novel your focus is narrowed for you, there's nothing going on that isn't on the page you're reading.
In terms of how many times I'll watch something, the number is really limitless. When I was about seven or eight, I got Babes in Toyland for Christmas and I watched it everyday for months. I watched it with such regularity in fact, that I had a friend who used to come over about the same time each time she came and she never saw the beginning of the movie. I was always at the same part. The most I've ever watched a move in one day is twice, though.