1. A method comprising: receiving a request from a passenger in a taxicab for a ride to a first destination; commencing the ride to the first destination; displaying a message to a passenger receiving the ride in the taxicab to the first destination, in which the message contains an offer of a voucher which is redeemable for credits at a casino at a second destination, in which the voucher may be redeemed for a first value of credits; receiving an acceptance of the offer from the passenger; charging the passenger a second value for the voucher and the ride, in which the second value is less than the first value, whereby the first value and the second value define a discount for the voucher; and outputting a receipt that represents the voucher, in which the receipt includes indicia indicating the first value and the casino.