Conversation with a friend this morning,

"Any idea how much a policeman's motor bike helmet costs?" he asked

"Don't know, I guess around £400."

"No," he said, "£450."

"How the bloody hell do you know that?"

"Well," he said, with the air of resignation that only comes after 20 years of marriage, "The hemet was sitting on the policeman's motor bike when ***** reversed into it."