RFID (radio-frequency identification) tags will replace bar codes in the not-so-distant future. Giants like Wal-Mart, Procter & Gamble, Gillette, and Kraft are betting that RFID will revolutionize supply-chain management. This Wired article takes a look at the supermarket of the future and explains how RFID technology will make it happen. Wired 12.07: Attention, Shoppers: You Can Now Speed Straight Through Checkout Lines!