The VeriChip can be hacked.

"This revelation along with other worrisome details could put a crimp in VeriChip Corporation's planned initial public offering (IPO) of its common stock," say Katherine Albrecht and Liz McIntyre.

The anti-RFID activists and authors of "Spychips: How Major Corporations and Government Plan to Track Your Every Move with RFID" make no bones about their objection to VeriChip's plans to inject glass encapsulated RFID tags into people.

But now they've discovered information that could call VeriChip's entire business model into question.

"If you look at the VeriChip purely from the business angle, it's a ridiculously flawed product," says McIntyre. She notes that security researcher Jonathan Westhues has shown how easy it is to clone a VeriChip implanted in a person's arm and program a new chip with the same number.

Westhues, known for his prior work cloning RFID-based proximity cards, has posted his VeriChip cloning demo online at http://cq.