On his way home from work one day a husband goes into the bookstore and sneaks a look at "The Joy of Sex" to find a new position to try with his wife.

He gets home and says to his wife, "I found a new position for us to try. It's called the Wheelbarrow."

"The wheelbarrow?" says his wife. "What's that?"

He says, "Remember when we were kids and you would walk on your hands while I walked behind, holding your legs up? It’s like that."

She says, "I'll do it, on two conditions. One, if I start to feel uncomfortable at all, we stop."

He says, "Of course. And what else?"

And she says, "We don't go past my mom's house."