This sort of program has been discussed before. As nice as it sounds, it would take an awfully long time to get anywhere earning one mile per shopping dollar spent. For a much better solution, I highly recommend shopping through ebates, where you earn cash rebates of up to 30% on every purchase. I just received my third check from them last week like clockwork (they pay quarterly). Because they invented the concept of rebating 100% of commissions paid back to the consumer, they are the largest affiliate of numerous larger websites. This means they always receive the largest commission possible, and that always goes directly back to you. Earlier this month, for example, when Healthshop.com was offering a 50% commission, other affiliates were probably rejoicing over all the money they'd be making while ebates was offering 50% off to all. So on a $100 order, which would you prefer: $50 cash or 100 miles? Exactly.