Mr Harkness walks into a bank London and asks for the loan officer. He says he's going to Europe on business for two weeks and needs to borrow £5000. The bank officer says the bank will need some kind of security for the loan, so Mr Harkness hands over the keys to a new Rolls Royce, which cost a quarter of a million pounds.

“The car is parked on the street in front of the bank,” says Mr Harkness, “and I have all the necessary papers.”

The bank officer agrees to accept the car as collateral for the loan. After Mr Harkness leaves, the loan officer, the bank's president and all their colleagues enjoy a good laugh at the man for using a £250,000 Rolls Royce as collateral against a £5,000 loan.

One of the employees drives the Rolls into the bank's underground garage and parks it there. Two weeks later, Mr Harkness returns, repays the £5000 and the interest, which comes to £15.41.

The loan officer says, "Sir, I must tell you, we’re all a little puzzled. While you were away, we checked you out and discovered that you’re a multimillionaire. Why would you bother to borrow £5,000?"

The man replies, "Where else in London can I park my car for two weeks for only £15.41?"