Are these things rfid under another name? If so, what rfid tech do they use? I have an rfid tag implanted in my hand that I'd love to find a use for in this context :)
As I understand it, NFC is similar to RFID, but RFID provides one-way communication, while NFC provides two-way communication. Someone please correct me if I'm wrong.
yes - but they are passive and short range. this is now known as "near-field communication'