A Faraday Cage For Your Wallet
And you thought those aluminized mylar wallets were just for geeks? Turns out they could be playing a much more useful role, as chronicled in this Washington Post article “The Electronic Pickpocket Stoppers.” “According to some security gurus, even when there is no receiver in the vicinity, your digital secrets are leaking merrily from the cards in your wallet, like sound from a radio that you can’t turn off….As weird as it sounds, wrapping your passport in tinfoil helps. The tinfoil people, in this case, happen to be correct.”
The article goes on to discuss a number of metal-lined wallets designed expressivel for the purpose of blocking out radio frequencies, including the $225 Italian Leather Teju Lizard Embossed Travel Wallet. Of course, rather than forking out all that dough for a luxury model, you could just make your own! Instructables has step-by-step instructions for a DIY aluminum foil RFID Blocking Wallet — photos included. And Dustin Kirk has posted instructions for a duct tape/aluminum foil RFID block wallet as displayed in the photo posted in this blog.