The Audio Commentary is great, there is a short montage of deleted scenes that's like 10 minutes long, and there's like a 30 minute making-of thing that is really fun to watch.
But the best extra is the fart-track, where the filmmakers did nothing but add "extra farts" to the movie. I've watched the fart-track all the way through a couple times and there are some really great farts (lol I mean parts
) to it