Mr. Miller

A man enters the saloon and asks, "Who is the chap named Miller?!"

"I am Miller," answers an old man sitting at the bar.

The man at the door walks to Mr. Miller and knocks him down. Then he leaves the saloon. Mr. Miller rises, sits on his chair again and starts laughing.

"Why are you laughing?" asks the bar keeper. "I would not find it funny to get knocked down."

"I played a prank upon him," answers the old man. "My name is not Miller."