Gary and John are in a sauna.
Gary says to John, "Do you want to see a magic trick?"
John says "Sure."
"OK. Face away from me and get down on your hands and
knees"
John turns around and gets down on all fours.
"There," says Gary, "...does that feel like you've got
a thumb up your ass?"
"Yes!" Replies John

Gary waves both of his hands in the air, "Magic!"