A family of performers walks into a booking agent's office..., and that's as much of the infamously filthy joke that comics pass between themselves as we can say. But 100 comedians-among them Penn Jillette, George Carlin, Gilbert Gottfried, Chris Rock, Sarah Silverman, and the "South Park" kids-share their profanity-filled renditions of the show biz shibboleth in this side-splitting performance essay on the nature and appeal of "dirty humor." WARNING: contains "unspeakable obscenity"; adults only.