More stuff off my site!
Excellent, easy to read series on RFID or Radio Frequency IDentification devices. They're those tiny, autonomous tags that WalMart is thinking of using to electronically track its inventory and possibly for checking out. You'd take your shopping cart to a RFID enabled register and it would scan by radio each product's tag. The whole cart at one time! Put your credit card in the register and off you go. This same technology lets cars zoom by toll booths without stopping. A RFID device communicates between your car and the electronic toll booth. When you pass by the toll gets taken out of your account. Neat stuff:
http://www.mobilein.com/RFID/RFID-1.htm (external link)