RSA Security has demonstrated a prototype of a new privacy technology which will block RFID readers from accessing data on RFID tags. The new technology, called the RSA blocker Tag, jams radio frequency signals:

"A fully developed RSA Blocker Tag will work by "spamming" any RFID reader that attempts to scan tags without the right authorization, thereby creating a hostile environment for the reader. When ordinary RFID tags are in proximity to an RSA Blocker Tag, they benefit from its shielding behavior; when the RSA Blocker Tag is removed, the ordinary RFID tags may be used normally. Thanks to its selective nature, the RSA Blocker Tag helps prevent unwanted scanning of purchased items, but does not interfere with the normal operation of RFID systems."

The company's press release makes it clear this is still a prototype and not yet for sale. A U.S. patent application is pending.

Sounds a little like the old Romulan cloaking device in the original Star Trek, doesn't it?