Not a movie, but SEINFELD referenced THE GODFATHER several times.
Two references off the top of my head are George, "when I try to get out, they pull me back in", and Jerry, "My house, where I sleep, where I come to play with my toys".
Also, the episode where Jerry and Elaine are to be Godparents and they just can't find a good moile (spelling?).
"I got news for you. If it wasn't for the toilet, there would be no books." --- George Costanza.
