A poor old lady answered a knock on the door one day, only to be confronted by a well-dressed young man carrying a vacuum cleaner.
"Good morning," said the young man. "If I could take just a couple of minutes of your time, I would like to demonstrate the very latest in high-powered vacuum cleaners."
"Go away!" said the old lady. "I’m completely broke and wouldn't be able to afford it!" and she proceeded to close the door.
Seeing his potential sale disappear, the young man wedged his foot in the door and pushed it completely open. "Please Ma'am, don't close the door yet," he said. "Not until you have at least seen my demonstration." And with that, he emptied a bucket of horse manure onto her hallway carpet. "If this vacuum cleaner does not remove all traces of this horse manure from your carpet, Madam, I will personally eat the remainder.
"The old lady, seeing the filthy mess on her carpet, stepped back and said, "Well let me get you a fork, ’cause they cut off my electricity this morning."