All you have to do this Saturday is walk into a retail store, bust out that lovable smart phone and use Amazon’s Price Check app on any unsuspecting in-store item. In exchange for your scanning services, Amazon will offer you a discount of five percent (or up to $5) on select items in its music, toys, electronics and other product divisions – you’ll have a maximum number of three scans. This program represents Amazon’s latest attempt to sneak into the brick and mortar space, while scavenging data on its competitor’s prices. All in all, a clever little way from Amazon in entering our mobile hearts. The campaign will begin on 9:00 PM (PST) Friday and will come to a close midnight on Saturday. See the source for more details.