This isn’t like the scanners in the grocery store where you just do a quick swipe… This is snapping a picture of a bar code with the Treo camera at just the right distance with good lighting and without moving too much… so forget opening up your own grocery store. Still, it’s pretty nifty to see somebody make the Treo do something so far away from its intended purpose.
Maybe you can want to get all the ISBN book numbers of every book on your bookshelf, for insurance purposes? You could use this, although typing the ISBN numbers is probably faster. 🙂