Future Stock RFID tags -- tiny chips attached to antennae that store remotely readable data -- are hardly a new invention. But, until recently, businesses and government agencies were hard-pressed to ...

[pc486] sent in his hack that uses an ATtiny85 to act like an EM4102, a chip used for RFID tags. Minimally, all that is needed is the AVR and a coil, but he recommends some filtering capacitors.