...apparently there's some evidence that implanting RFIDs can cause cancer.

http://arstechnica.com/news.ars/post/20 ... wdown.html

And the guy that was in charge of the FDA approving RFIDs for implantation into humans left his job at the FDA for a fat job at an RFID manufacturer. Isn't that convenient.

The cancer rate appears to be 1-2%, so it's nothing earth shattering, but it probably shouldn't have been approved with further study.