A chap goes to a night club and is refused entry on the grounds that he's not wearing a tie. "Hang on a minute" he says to the doorman, "I think I've got one in my car, I'll just go back and get it. So our chap goes back to his car and after many minutes of searching fails to find a tie. All he can find is a set of jump leads so he wraps them round his neck, ties them in a knot and returns to the club. "I couldn't find a tie, will this do?" he asks. The doorman looks him up and down and says "well I guess you can come in, but you'd better not start anything".