Dynamic pricing offers many advantages for marketers. For example, Internet sellers such as Amazon.com can mine their databases to gauge a specific shopper's desires, measure his or her means, instantaneously tailor products to fit that shopper's behavior, and price products accordingly. Catalog retailers such as L.L.Bean or Spiegel can change prices on the fly according to changes in demand or costs, changing prices for specific items on a day-by-day or even hour-by-hour basis. And many direct marketers monitor inventories, costs, and demand at any given moment and adjust prices instantly.