I just read this awesome post over at CrunchGear about smart shopping carts:
Shopping carts rigged up with a touch screens and barcode scanners might find their way into London supermarkets soon, according to Reuters. You'd simply scan an item and get a readout of how many calories, fat, and whatnot it contains. It'd be similar to looking at the back of item with your eyes except with a few more steps involved.
Cumbersome? Yes! But pretty nifty