Radio Frequency Identification Devices (RFIDs) are essentially glorified barcodes – tiny microchips with an antenna attached which retailers can use remotely to manage inventory and stop theft. They can also be used to trigger promotional messages when you pick up a product in store (like in the Prada store in New York). In the future RFID readers could scan your bags as you leave a store and automatically take the money from a suitably enabled mobile phone (or a tiny chip located in your forearm or teeth) which is linked to your bank or credit card. RFIDs have a myriad of other uses too, such as remote monitoring (healthcare) and baggage tracking (transport). In Japan a school even used RFID readers to tell parents that their children have arrived safely at school. Expect a major surge in RFID adoption in 2007+.