"The world of RFID is like the Internet in its early stages," says Ari Juels, research manager at the high tech security firm RSA Labs. "Nobody thought about building security features into the Internet in advance, and now we're paying for it in viruses and other attacks. We're likely to see the same thing with RFIDs."

[...] Most commercial RFID tags don't include security, which is expensive: A typical passive RFID chip costs about a quarter, whereas one with encryption capabilities runs about $5. It's just not cost-effective for your average office building to invest in secure chips.