I will start you off.
A guy walks into a talent agency. Talent agent says, 'Whaddaya got for me, kid?' Guy says 'I have a family act.' Talent agent says 'Okay. What do you do?' Guy says...
[your joke here.]
Talent agent says, 'Wow, hell of an act. What do you call it?'
Guy says, 'The Aristocrats.'
Please to be filling in the blank.
This post inspired by robyn_ma, whose version is truly impressive, but friends-locked. (EDIT: But she has reposted it here!)
EDIT: You may feel free to pimp this. I wish to see many jokes, oh yes.