Ha, that was a good one!

Whoo-hoo: got it in 6.

Oh - a classic:

http://www.albinoblacksheep.com/flash/end

hmm... i like this one

http://www.weebls-stuff.com/toons/Late+Night+Shopping+2/

A woman goes to market, to buy some fish. She buys five fish and the fishmonger tells her she has to pay 11 euro. "I don't have that," she says. She gives him a 20 euro bill. Then she gives him a 2 euro coin as well.
"That's nice," the fishmonger says. "Now I can give you back one 10 euro bill and one 1 euro coin, making 11 euro." The woman looks at the money in her hand and says: "Wait, I can pay you the 11 euro, I have it here."
"That's great," the fishmonger says, and he takes the 11 euro, and gives the woman her 20 euro bill and the 5 fish.
Who is the fool?