Is there an API that allows lookup of product information by UPC? I know that Amazon has the Product Advertising API but don't think it can be used for any purpose other than sending traffic to amazon.com as per their license agreement here. Specifically, my application would
not have the principal purpose of advertising and marketing the Amazon Site and driving sales of products and services on the Amazon Site
Does such an API exist that I can do anything I want with the data?
UPDATE
I would want to use the API for my application, not create create such an API.
UPDATE2
Users would enter the UPC, the application would use this API I'm asking about to retrieve information about that product.