The films that you watch many times, and always affect you.
I have an almost endless list! But I'd have to say, the movies that I love the most are Jurassic Park, 2001: A Space Odyssey, Play Time, Lawrence of Arabia, Monty Python's Life of Brian and Rear Window. Trust me, I could name a hundred more, but these are the ones that come to mind.
How about you? What are some of your favorite movies? A Top 10 would be ideal. :)