A man is in his car in a traffic jam when a guy taps on the window.
“Some terrorists have kidnapped Gordon Brown and Alistair Darling,” the guy says. “They are demanding £10m or they will pour petrol over them and set them alight, so we’re going from car to car to raise a collection.”
“What’s everyone else giving?” the man asks.
“Oh, about a gallon,” comes the answer.