A Irish hobo walks into a pub in London, and approaches the barman. "If I show you an amazing trick, will you give me a free drink?" "Sure" says the barman. So the hobo takes a tiny rat from his pocket along with a tiny piano. The rat cracks his knuckles and begins to play the blues. "Wow", says the barman, "thats impressive, what are you having? " The hobo says, "hold on a minute, if I show you and even better trick, will you give me free drinks for the rest of the night? "The barman agrees, and the hobo pulls out a frog and sets it beside the rat. The frog begins to sing along with the rats music. A guy at the end of the bar sees this and rushes over to the hobo. "I'll give you £50,000 for the frog!". "Sorry" says the hobo, "hes not for sale". "£100,000" says the guy. "No, look I'm not interested." "£500,000!" exclaims the guy. Finally the hobo agrees. The barman, dumbfounded, says, "are you nuts? You just sold that frog for £500,000 when he's clearly worth millions!" "Ah" says the hobo, "you see, the frog is nothing. The rat is a ventriloquist."