ers to sidetrack coun- terfeiting, achieve improved crowd flow management, and ensure that people sit in their assigned seats. Likewise, RFID could help parents track their kids' movements around an amusement park. At Hyland Hills Waterworld, a water- park in Federal Heights, Colorado, RFID wristbands have taken the place of money and credit cards. "People don't carry their wallets or purses when they're in the pool," says Bob Owens the park's assistant manager. "We needed a way to allow people to spend money easily while in the park." ASSET TRACKING The wristbands work like a wearable debit card, allowing people to spend money simply by waving their hands past readers located at snack bars, gift shops, and other park venues. At the end of the day, the wristband is either thrown away or saved as a souvenir. Although more expensive than barcode imprinted wristbands, the RFID devices aren't vulnerable to damage caused by pool chemicals, the sun, or stretching. "The fact that they're disposable means that that we don't have to worry about the band's long-term physical integrity," says Owens. More ominously, authoritarian governments could use implantable tags to track people and create lists of places they've visited. "There is a dark side to this technology," says AMR Research's Abell. 6.4.3 RFID in Retail To find the "store of the future," you'll have to travel to Rheinberg, Germany. That's where METRO Group, the world's fifth largest retailer, has created a convenience store that's designed to serve as a real world test bed for a variety of advanced retailing technologies. The Extra Future Store, as the outlet is formally known, aims to showcase promising systems that can benefit both shoppers and retailers. Very little inside the store isn't touched by some type of technology. Cases, shipping pallets, shopping carts, and individual products are all tagged with RFID devices that allow everything from sales tracking to automatic inventory replenishment to preventing congestion at the checkout line. Consumers can a