The technology that will see groceries remain in the trolley at the supermarket checkout could also see people's movements secretly tracked, thanks to a tiny chip implanted in their clothes.
Radio Frequency Identification (RFID) has been around for decades. The British, for example, used it in World War II to identify incoming aircraft as friend or foe. But in recent years someone came up with the idea of using it to identify goods, then putting the data on globally networked databases, announcing the arrival of the "Internet of Things". Then someone else thought of putting the technology into people. Suddenly, an old technology had new life.
RFID uses tiny pieces of hardware called transponders, or "tags", which are essentially microchips that feature an antenna. These tags transmit and receive radio signals to and from nearby scanners. Goods can be tracked along a whole supply chain, not just from factory to warehouse to shop, but also into your home and even into landfills.
It may sound like future talk, but RFID is already out there - in car immobilisers, toll roads, passports, library books, clothing, cows, even fish. There are over 10,000 RFID tags in every Airbus A380, the world's largest passenger aircraft. But the most visible evidence of RFID in your life in the future will probably be at the supermarket.
German grocery giant Metro has successfully demonstrated the retail holy grail of checking out groceries without removing them from the supermarket trolley. Farewell, then, checkout staff. For manufacturers, their grail is also within reach - a "sell one, make one" supply chain. In another words, as sales of DVD players at global checkouts speed up or slow down, so would the synchronised production line in China or Vietnam. Virtual zero storage makes JIT (Just In Time) warehousing look tardy by comparison.
In Europe, early adopters like Tesco have staged some high-profile pilot projects. The supermarket chain tagged packs of Gillette Mach3 razor blades so that staff were automatically alerted to stock levels, sell-by dates and whether a product had been paid for when it left the shop. Then Benetton started sewing RFID tags into its clothing.
This was too much for privacy advocates such as Caspian (Consumers Against Supermarket Privacy Invasion and Numbering) and NoTags. Websites appeared that encouraged consumers to boycott Tesco, Gillette, Benetton and other RFID adopters. Retailers found themselves issuing reassuring press releases about privacy. Other companies put the brakes on RFID trials.
But concerns about nosy razor blades were nothing compared to worries about the RFID-tracking of humans. In California recently, a school decided to RFID-enable students' ID cards, but didn't bother to tell pupils or parents. Once the truth came out, parents complained, negative publicity snowballed and the project was canned.
A few days later, the University of California revealed that it is RFID-tagging cadavers in an effort to cut down on the theft of body parts for sale on the black market. Dissect me, Trade Me.
California has earned a reputation as the world's laboratory for such experimentation, so it was no surprise that a Californian company, the Verichip Corporation, was the first to get paid to implant RFID tags into people. Verichip injected rice-grain-sized tags into the arms of the Mexican Attorney-General and various staff members - in order to control access to a new government facility in Mexico City.
More recently, a Glasgow bar has started encouraging customers to "get chipped". Owner Brad Stevens boasted, "By the time you get to the bar, your tab is set up, your favourite drink is poured and the bar staff can greet you by name."
Convenient, sure. But Chris McDermott, the director of NoTags, commented that "having the chip inserted under the skin is the same as having a barcode tattooed onto your forehead, only worse".
On top of the privacy implications, the Scottish Government was also concerned that just waving your arm to buy another drink may cause some people to drink excessively. The bar's name? Bar Soba.
But RFID can be good news, too. Since the mad cow disease and foot and mouth disasters, RFID-tracking of animals has been a major plank in the British Government's strategy to track meat from "farm gate to dinner plate". Today, over a million pets and farm animals worldwide have RFID tags in or on them, so Rover or Daisy can easily be tracked if they wander off.
And few could object to the Australian hospital that has introduced a non-invasive, RFID-based baby-tracking system in its maternity ward, in response to the kidnapping of a newborn in 2003, or to the launch of the "SurgiChip" in the US, an adhesive RFID tag that aims to prevent "wrong-site, wrong-procedure and wrong-patient surgery".
Meanwhile, back at the supply chain, the US Department of Defense and retail behemoth Wal-Mart suddenly told hundreds of their suppliers late last year to begin RFID tagging, "or lose our business". Companies worldwide sat up and took notice.
But is RFID really a threat to our privacy? Blair Stewart, New Zealand's Assistant Privacy Commissioner, cites concerns raised by his counterparts in the European Union. They expect RFID technology to become one of the main bricks of a future "ambient intelligence environment", a phrase that Stewart says he finds "somewhat chilling".
"The technology in itself is neutral," says Stewart. "It's what people do with it that concerns me. Once you get beyond the checkout, what safeguards do we have that the tags are no longer active? Transparency is important, too - should goods explicitly state that they contain these tags?"
GS1, the international standards body that promotes the new Electronic Product Code (EPC) network, is proposing a New Zealand RFID Code of Practice to promote responsible industry behaviour. The code may approve the use of "kill codes" (PIN-protected commands that permanently disable RFID tags) to allay consumers' privacy fears.
The drawback is that "dead" tags can't provide consumers with the envisioned benefits, such as receipt-less item returns, product recalls and smart appliances like the famous fridge that uses RFID to automatically order more white wine.
Is RFID about to take off in New Zealand? "Companies here have been in a watching and waiting mode," says Gary Hartley, manager for strategic initiatives, GS1.
"But since the Wal-Mart decision, there has been an upsurge in interest, especially from logistics companies. Identifying what's in a stack of six shipping containers without having to climb a ladder is an attractive proposition."
The Warehouse, Tranz Rail, Progressive and Fonterra are all using or thinking of using RFID, but other Kiwi companies known to be dabbling are keeping a low profile. A new library at Auckland's Botany Downs is the first in New Zealand to use RFID. Its 30,000 tagged books will be automatically scanned in and out, and library staff can ascertain whether books are out of sequence on shelves simply by running a handheld scanner along them.
A leading Kiwi RFID star is Auckland-based Sandtracker, which has several interesting RFID projects under development. One example is sports event company CodeNZ, which is using Sandtracker's tags for athletes' bibs. Large groups of runners crossing a radio beam have been individually timed and counted successfully. Elsewhere, there is talk of RFID tags inside rugby and soccer balls to reconcile "over the line" disputes.
Globally, the market's verdict on RFID may still be in doubt, but it's clear that major retail players remain sensitive about privacy issues. However, the huge investment that stores like Wal-Mart and Tesco continue to make in RFID suggests that they see consumer fears evaporating. Sailing through a checkout in seconds sounds good to most shoppers in a hurry.
As far as tagging humans goes, how many parents would say no if it meant that their children's safety was at stake? If it meant instant notification on your cellphone that something or someone prevented your child arriving at school today?
In today's insecure world, the unthinkable can soon become the everyday, but the question remains - is RFID a game of tag too far?