Bart: Is this cel worth anything? [gives him cel with arm on it]
Dealer: [looks at it, sighs] Let me show you something. This -- this is
a Snagglepuss drawn by Hic Heisler. It is worth something.
This -- this is an arm, drawn by nobody. It is worth nothing.
Bart: Can't you give me anything for it.
Dealer: I can give you this telephone. It is shaped like Mary Worth.
Dealer: No groaning in my store.
-- Or was that "no Groening"?, "Lady Bouvier's Lover"