Photocopying a picture of your bare, naked butt and sending the picture via fax to someone who deserves it or is getting on your case. A good retaliation strategy for fax spam, or spax.
"Yo, I sent an ass fax to that travel agent that keeps killingtrees with his crappy spax."
When someone's behind is so large that it would require a seperate conveyance to carry it around.
An electric cart available at Wal Mart or other large retail outlets for obese pigs to carry their wide load butts around the store.
"Junior! Run into the store and go get your mama an ass taxi,
while I find a handicap spot."
A small goblin-like animal with a Hitler mustache that resides inside a person's ass. At night, ass nazis leave their dwellings and venture outside to steal your underpants. See also: "Underpants Gnomes".