Some crazy folk implanted a RFID chip in his hand as depicted in this Flickr picture: Here is explained the point of this.

FAQ (frequently asked questions) Q: can't they track you?! A: no. the read range is only 2 inches max. even with a high powered reader, the chip itself does not have the capability to transmit farther than a couple inches tops. this makes it very difficult to scan my RFID chip without me noticing, and it's definitely not possible to scan it just by me walking by a sensor or something. It has to be pretty deliberate.

Q: why the hand, and your left hand to boot? A: well, I reach for my car door handle with my left hand, and I can get used to opening my front door with my left as well. plus, being right handed, my left hand is far less likely to get crushed, mutilated, or otherwise damaged... and I'm sure granules of crushed glass, silicon, and other metals could cause health complications, aside from having a crushed hand.

Q: did you do it yourself? A: hell no. a client of mine is a doctor and we traded services.

Well, it's crazy :( Some odd experiment...