I used to do a lot of babysitting, so I saw the first Harry Potter movie about a billion times. Same with the Power Rangers movie and Howard the Duck.
Then I did the whole film school thing, so I've seen Man With a Movie Camera, The Cabinet of Dr. Caligari, Citizen Kane, and 8 1/2 several times each.
On my own though:
Battle Royale, Back to the Future, Who Framed Roger Rabbit, Labyrinth, Army of Darkness, Seven Samurai, and the old cartoon Transformers movie.