You may want to check out the Assylum Street Spankers.   They have a bunch of "r" rated material like "If you love me, you'll sleep on the wet spot" and "Scrotum" and many others.

Also try Camille West.   Very funny lady with some questionable tastle.    She has been touring with the 4 Bitchin Babes for the past several years.    I went to a workshop of hers a few years ago, and she said that people need a sense of humor today- today more than ever.   If you do funny material, she said that people somewhere will come up to you and tell you its offensive.    100 people may laugh, but one may find it offensive.   Her usual answer to that is "And your point is"

There is also a tape/Cd of twisted Christmas songs.   "The rest room door said gentleman" and many others.   Surely bound to make most people laugh and offend some others.