A guy hears a knocking on his door. He opens it up, and no one is there. He looks all around and he finally sees a little snail sitting on the doormat. He picks it up and throws it across the street into a field.
Ten years go by, and one day he hears a knocking on his door. He opens it up and no one is there.
He looks all around, and he finally sees a little snail sitting on the doormat.
The snail looks up and says, "What the hell was that all about?"