Good Chips, Bad Chips, Hacked Chips
The same day that the Washington Post runs an article on the use of implantable RFID chips for medical record keeping, the NY Times has a piece about how RFID chips can be infected with computer viruses.
That'd be quite a hack ... Either collecting or changing the medical history of someone by infecting their RFID chip with a virus, or using people as Trojan Horses to introduce viruses into hospital computer systems for nefarious or malicious purposes.