I don't know how many of you watch "The Green Room with Paul Provenza" on Showtime. It's a discussion show about comedy. Many of the comedians are atheists, including Provenza. On one of the episodes he makes a great joke about the difference between Shiites and Sunnis being a "clerical error". Video provided below (it's at the end of the two minute clip):
The Green Room is a great show and you should check it out if you haven't already.