Author Glyn Moody has written an article over at Private Internet Access regarding implanted microchips, such as RFID and NFC responders. Initially seen as one-off bad ideas, these projects centered around implants are starting to come more frequently and with stronger incentives. If allowed to become more common there is a danger that they will become normalized and extended to uses that are less and less benign.
Source: Private Internet Access : After call to implant microchips in people awaiting trial, are they about to become the next threat to our privacy? [privateinternetaccess.com]