A man goes to a store to buy some kidneys. He says to the shopkeeper, "I'd like a pound of kiddillies, please." The shopkeeper says to him, "You mean kidneys, don't you?" The man says, "I said kiddillies, diddle I?"
La Forge did not find the joke particularly funny. Upon further discussion on the matter of the humor, Data later had a slip of the tongue when speaking of all the jokes he had learned, and said, "Includling the kiddillies..." prompting La Forge to find the inadvertent spontaneity of Data's joke to be funny. (TNG: "Code of Honor")