Toppan Printing has developed a paper that can prevent the data maintained on RFID cards from being read by unauthorized readers. Essentially a tin-foil hat for your RFID cards, the paper has a very thin layer of metal inside (the paper being only about 0.2mm thick) which effectively blocks any RFID read attempts on the card inside. Perhaps a similar material will be used in the much discussed forthcoming US Passports which will theoretically make use of RFID and also a similar in-concept RFID shield.

Toppan Develops Paper That Protects RFID Data [RFIDinJapan]