A guy is sitting at a bar, staring at the sexy bartender. He slaps a 10 spot on the table and says, "I bet I can keep an eye on this drink while I go to the bathroom." She knows the bathroom is around the corner, so she accepts the bet.
He takes out his glass eye, places it beside his drink and goes to the bathroom. When he comes back, he pockets the money and makes another challenge.
"Betcha I can bite my own ear," the guy says. She accepts, and he takes out his false teeth and nips his ear. Once more, he scoops up the money.
"OK," he says, "I'll give you a chance to win back your money. I bet I can make love to you so tenderly that you won't feel a thing."
She knows this bet is a sure thing, so she accepts. The guy climbs behind the bar, lifts her skirt and begins.
"I can feel you," she giggles.
"Oh well," he says, "You win some, you lose some."