This is one of the best uses of FLARToolkit that I have seen to-date. I’m glad to see people making use of AR to solve actual problems, and not solely for the wow factor. You can’t get much more un-wow than a USPS priority mail box, but a simple app like this could help make everyday decisions like how to ship that recent eBay sale all that much easier.
I see a lot of promise for AR in the home, helping people answer questions about how well real objects will work in their personal space before schlepping the actual atoms.
Try the app out here.