RFID technology is used to identify unique individuals, so it is possible to create an interface enabling you to log onto your computer using an RFID transponder. However, I am unaware of any products currently on the market that provide the hardware and software required to do this.
Some techies have written articles explaining ways this might be accomplished (see Logging Into Windows XP Using RFID). We do not know whether the suggested solutions work, however, or if they expose your system to hackers. I would point out that there is a potential drawback to using RFID in this manner: If you lose your ID card or other type of RFID transponder and someone finds it, they can access your computer. With a memorized personal identification number, only you have computer access.
There is a potential positive as well: You could set up a system to read a tag on your chest as you sit at your computer. When you walk away, the system could automatically go into sleep mode, requiring either a PIN or a password before awakening. Currently, most systems go to sleep after a few minutes, leaving an opportunity for someone to jump on your computer and use it while you are away.
—Mark Roberti, Editor, RFID Journal
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