Changing prices digitally

  Imagine that you walk into a supermarket where the prices for the products were all digitally displayed right under the product instead of the paper sticker. It would display it like a watch. It could easily be updated if there was a price change through a computer. There would be no need to have someone printing tickets and walking around looking for it to change the sticker. Products that aren't updated would have to sell for the actual price displayed if customer gets mad.