Cowgirls, Ducklings and Pussycats (or anybody else that wants to try):
Wear a crotch rope for 24 hours:
http://www.ehow.com/how_8778940_tie-crotch-rope.html
Ducklings and Pussycats should use the rope to keep a plug in their asses for as long as they can throughout the 24 hours. Just prior to removing the rope, you must sit in your bath and piss 'through' the rope.
Cowgirls, once you are ready to remove the rope, try to bring yourself to orgasm (or edge if you are not permitted) by manipulating the rope, without directly touching yourself.