And islands of RFID use directly touching the consumer are already appearing. Singapore’s National Library chipped all of its books a few years back, and now patrons check out their own books while "smart" book drops automatically check in returns.

Tomorrow’s RFID chips won’t just spit out serial numbers; they will also carry data and myriad sensors, transforming inert objects into "smartifacts"—intelligent artifacts that interact with the surrounding environment. Add this all on top of today’s search engine craze, and I’ll bet we’ll eventually have "IndexBots" running around the landscape hunting and cataloging every RFID chip they find.

No wonder consumer privacy advocates are already fretting over RFID. The privacy implications of a smartifact world are indeed as chilling as they are unpredictable. RFID itself is not privacy-eroding—the risk is determined by the architecture of the RFID standard and supporting systems. But developments in other areas offer no comfort. Consider the FasTrak electronic toll system, a system that could have been made anonymous, but instead dutifully tracks and records where and when cars cross toll points. The promise by developers that FasTrak would never be used for anything besides tolls has already been broken in California where additional sensors are being deployed to track FasTrak transponders to analyze and control traffic flow. Again, the public has been promised that individual data is not being preserved, but in these terror-obsessed times, one does not have to be a paranoid to react with a cynical snort of disbelief.

I suspect that the biggest challenge to privacy will not be from corporate or government push, but consumer pull. In the short run, the same consumers who fret about privacy will likely be happy purchasers of RFID-based home inventory systems. Even as they object, they will be sticking RFID chips on their pets and into their kids’ schoolbags.

And when in-store RFID deploys, proponents will inevitably establish links to in-home devices. Consider a future home-shopping scenario in which sensor-equipped refrigerators track what is used, generate and place shopping orders, and even warn consumers if the milk they are about to drink is old enough to have a driver’s license. Wary consumers could disable chips in the items they buy, but then they would have to do their ordering manually. Americans may seem to be privacy-hawks, but they are also lazy and suckers for anything that sounds like a deal. Given a devil’s choice between privacy and convenience, the vast majority of consumers will choose the latter.