Delta Air Lines has launched an online marketplace where its frequent fliers can use miles to pay for hotel rooms, car rentals and merchandise. Atlanta-based Delta is working with its credit card partner American Express to offer the e-commerce portal, where frequent fliers can redeem miles or a combination of miles and money. Other airlines also have online mileage stores.

For its SkyMiles Marketplace, Delta is using services from LoyaltyEdge, a business American Express started to help Delta and eventually other AmEx partners manage their rewards programs. Delta also maintains an online mileage auction site and a SkyMiles Shopping site where customers can earn miles by shopping.