Voodoo.

 There's a man and his wife, and they were having sex. But that wasn't enough for them, so the man decided that on his way home from work the next day, he would go to the "toy" shop, and pick something out.

 So the next day he goes into the shop, and the man at the counter asks, "Can I help you?" "What do you have in stock?" asks the man. The man at the counter pulls out a box from under the counter, but doesn't open it. "Well, we've got vibrators, and chains, and...." he goes on with a long list. "No." the man replies. " I want something unusual for my wife." "Well," the other man says," we do have one  thing. The Voodoo dick." "What?" asks the man.

 So the counter-man opens the box. "Voodoo dick, door." he says, and it jumps out of the box, and humps the door. "Voodoo dick, box." says the man again, and it goes into the box. The man is so excited to get it, that he buys it, and rushes home. He shows his wife what he got, and they start right away.

 The next day, when the man is at work, his wife decides to use it, but later, can't figure out how to turn it off, or make it stop. So she decides to drive to her husbands work, so he can stop it.

 On the way there, she speeds, and is pulled over by a cop. When he asks what's wrong, she tells him about the Voodoo Dick. "It's under my skirt officer." "Yeah right." he says, and walks back to his car. "Voodoo dick my ass." he mutters.