A viola player decides that he's had enough of being a viola player--unappreciated, all those silly jokes. So he decides to change instruments. He goes into a shop, and says, "I want to buy a violin."
The man behind the counter looks at him for a moment, and then says, "You must be a viola player."
The viola player is astonished, and says, "Well, yes, I am. But how did you know?"
"Well, sir, this is a fish-and-chip shop."