Check out the Bar Codes

Researchers from Sunchon National University in Suncheon, South Korea, and Rice University in Houston have built a radio frequency identification tag that can be printed directly onto cereal boxes and potato chip bags. The tag uses ink laced with carbon nanotubes to print electronics on paper or plastic that could instantly transmit information about a cart full of groceries.

And if you're worried that others will know what you have (once the groceries are yours), there's a way to maintain your privacy:

And for those who would rather not have their food broadcast radio waves after getting it home, fear not. Tour says the signals can be blocked by wrapping groceries in aluminum foil.

It's easy to envision shopping with a grocery cart and then check out with a swipe of your credit card (or via your personal digital assistant like an iPad) and then just exist the store. In fact, it's possible that you simply swipe in to the store and when you leave, you just leave. The costs are automatically tallied, and charged or transferred from your account, as you depart.

This would lessen shoplifting, to an extent, too. To shoplift one would have to cover the product in tin foil. Not an impossible task, but it would take more effort than hiding an item in your purse. Of course, if your purse is coated with metal, well, I guess shop lifting would still continue.