It's been done with with many iOS devices before. In public, no less. Pretty much everyone has done it, but there's no shame in it. I am, of course, referring to using an iPhone/Pad's wifi (or 3G) capabilities to look up an item's price online while still in the store. Maybe it's to check for a better price or even to see if it can be "flipped" for a decent profit, but no matter the reason people do it all the time. Now TechCruch has pointed out a new app that makes the process super easy.
Amazon Student, along with a few other Amazon apps, enables users to do all that and more. A quick scan of a barcode is all it takes, really. The idea is that it makes looking for a good price on textbooks easy, but it works on just about everything sold en-masse in a retail environment. The big difference here is that it also allows users to scan their own items to sell on Amazon if they're eligible for trade-in. Just scan it, and if it's a "yes" then Amazon will pay for shipping and send out a gift card.
I think the word "neat" pretty much covers it.