Now THIS is hilarious. (Friday hilarity day!)

Watch this trailer for Mel Gibson's new movie:

http://www.apple.com/trailers/touchstone/apocalypto/large.html

About 3/4 of the way through, you'll see a fast-cut montage with a monkey screeching in it. Pause the trailer right after the monkey screeches, then use the frame back button in the player to move back a few frames. You'll know what's so funny when you see it.