Bid for how much you are willing to be bumped of a flight

Delta Airlines at Atlanta Hartsfield-Jackson Airport

Up to now if a flight is oversold airlines would make an announcement in the gate area looking for volunteers willing to take a later flight  in return for travel credits on future flights. Delta Airlines is taking a new approach by letting passengers silently bid on a bumped seat. If a flight is oversold passengers can name an amount, during check-in, they are willing to accept in return of taking a later flight. Delta would then consider the lowest bid to be bumped of the flight if it becomes necessary. Full story here.