"My favourite ticketing system was in Mumbai, India," Kim enthuses. "No one actually buys a ticket, but you can buy ‘ticket insurance’ from private entrepreneurs who work at the entrance of the station. The ‘ticket insurance’ is about half the price of a regular rail ticket. It gives you a guarantee that, in the extraordinary event that you are booked by a railways inspector for taking a free ride, your fine will be paid. A relative was once booked and the ticket insurer paid the fine exactly as promised."
Here is the link, and thanks to Brendan Leary for the pointer.