A snail goes into a car dealership because he wants to buy a car.
The dealer asks the snail if sees something he likes.
The snail says "Yes, but I will only buy the car if you paint a big white 'S' on each side of the car." The dealer is not sure and says he will have to sleep on it.
The snail comes back to the dealership the next day. The dealer says "Good news, I will sell you the car, but only if you tell me why you want me to paint a big white 'S' on each side."
The snail says "So that when I am driving by, people can point and say 'Look at that S-car go!'"