I remember seeing a StarWars parody, something about one guy playing all of the roles. It was pretty funny, I saw it at about the same time that Spamalot was out.
I love Monty Python and the Holy Grail... it's a classic movie, the part with the bunny with big, sharp, pointy teeth and when I can't remember the knight's name goes into the castle with all the girls, oh those scenes are the greatest!