Do credit cards that offer reward points work for that? or is it only retail programs?
I would suggest also looking at bookstores such as Barnes & Noble. Many bookstores look to readers who are giant purveyors of media and offer them rewards for purchasing books in order to keep them coming back. Since books are available from Amazon.com and other online venues, this is a method to deliver a sort of encouragement to stay with them and not leap off to a non-brick & mortar outfit.
