Someone brushes against you as you walk across the hotel lobby. You reflexively feel for your wallet. It’s there. But when you get back from dinner, the contents of your suitcase are all over the floor of your room and your laptop’s missing. How did it happen? The pickpocket who brushed against you used an RFID reader to copy the radio-frequency identification data from the smartcard key in your wallet — an easy trick, since the chip-based card contains an antenna and a power source, flinging your data into the air like a little pirate radio station. And the crook could just as easily have read RFID data from any chip-equipped credit or debit card, driver’s license, or U.S. passport. More bad news: While most RFID readers require proximity of 2 inches or less, a tweaked one can work from up to 69 feet away — that’s how vehicles whisk through the EZ-Pass gate on the highway. How, then, can you protect yourself? By stuffing those stupid smartcards into a protective wallet that blocks the signal. DIFRWear offers them in three colors, and when you actually want to use the card, simply flip open the wallet and expose it to the smartcard reader. Now life is a little less scary. The only safer course is to disable the card altogether.