A bloke walks into a bar with a rat and a frog. The bloke asks the barman if he can have a free drink if he shows him something amazing. "OK" says the barman, "But it must be truly amazing."
The bloke puts the frog on the bar piano and the frog begins to play the most amazing jazz.
"Wow!" says the barman. "That WAS truly amazing. Have a drink on me."
On finishing his drink the bloke asks "Can I have another drink if I show you something even more amazing?"
"OK." Says the barman. "If it is better than before, you can drink all night."

The bloke then sets the rat on the bar. The frog starts playing the piano and the rat sings along."

"Drinks all night for you." says the barman impressed.
An agent who has watched all this comes up to the bloke and says "I'll pay £1,000,000 for the frog and the rat."
"No deal" says the drunk.
"OK. What about £1,000 for the singing rat?"
"Done!" says the bloke.

"Are you mad?" says the barman to the bloke when the deal is done and the agent has left.

"Relax" says the bloke. "The frog is a ventriloquist."