* Photo: Plamen Petkov * 1// Saguaro cacti

On the landscaping black market, these succulents sell for more than $1,000. Arizona's Saguaro National Park plans to use RFIDs to track hot cacti.

2// Indian elephants

The New Delhi forest department requires pet jumbos be chipped to prevent trafficking. No parades until implanted.

3// Surgical sponges

One out of every thousand or so intra-abdominal surgery patients "retains" a sponge. Oops! With SmartSponges, docs can find stowaways by passing a wand over the body.

4// Mexicans

Security firm Xega uses GPS chips to track kidnapped people—a pretty big market in a nation where 6,500 were abducted last year.

5// Pirelli tires

A chip inside the new Cyber Tyre transmits info on road conditions and friction coefficients to the car's computer.

6// Clubbers

At Barcelona's Baja Beach Club, VIPs are injected with RFIDs linked to debit accounts, making wallets passé. Handy when all you're wearing is a thong.

7// Tokyo

The city aims to blanket itself with microchips—from bus stops to restaurants. Tourists may soon get maps, schedules, tips, and other info just by waving their cell phones.

8// Police badges

The Blackinton SmartShield badge hides an ID chip, preventing knockoffs. Good idea: Remember Terminator 2?

9// Inmates

Forced to release prisoners due to overcrowding, Britain wants to chip them. Cops would know if, say, a felon enters a school.

10// Cat doors

Kitty flaps are great—until you find a possum hanging from your towel rack. The Pet Porte waves through only preapproved critters.

Start Previous: Mr. Know-It-All: Disclosing DNA, Enrolling Friends in Rehab, Protecting Peepers on a PDA Next: Statgeist: Charting the Wired World Bush Administration: Dismiss RFID 'Mark of the Beast' Lawsuit

Geekipedia: RFID

Sleek and Sturdy Steel Wallet Keeps RFID Hackers at Bay

Not Just for Retailers, RFID Helps Track Rainforest Wildlife