In this day and age of faster home computers, people are churning out more and more movie quality spoofs. Two that I really like are the remixed trailers for Sleepless in Seattle and the Shining.
Oh then there is the amateurish ones like the music video for William Shatner's Lucy In the Sky With Diamonds
Links from kottke.org. Makes me wish I had a new compuer and get in on the fun!