The basic model would consist of a tiny GPS transceiver placed in a capsule and inserted under a person's skin, so that authorities could track him easily. Model B would have an extra function - a dose of cyanide to remotely kill the wearer without muss or fuss if authorities deemed he'd become a public threat.
http://snipurl.com/jut6y
From Information Clearing House
http://mindcontrol.twoday.net/search?q=chip
http://mindcontrol.twoday.net/search?q=implant