A company has developed an RFID tattoo, that has all the benefits of RFID implantation, but without the messy chip. The chip is replaced by a tattoo. The company is touting its benefits in traceability of the meat supply, but is also suggesting that it may be useful in soldiers:
Industrial Control Designline RFID Ink
... The ink also could be used to track and rescue soldiers, Pydynowski said.
"It could help identify friends or foes, prevent friendly fire, and help save soldiers' lives," he said. "It's a very scary proposition when you're dealing with humans, but with military personnel, we're talking about saving soldiers' lives and it may be something worthwhile."
I can't imagine anything more dangerous than tagging all soliders with a tracking device that may be hacked by the other side. Instead of saving lives, it may result in wholesale destruction. I wonder how long it would be before we saw RFID activated IEDs? Not long, I expect.
Thanks to Schneier for the link.