[Matt] has mixed up a batch of two RFID reading door lock systems. While the "door lock" part of the setup has yet to come into existence, the "RFID reading" section is up and running. By using the Parallax RFID readers (for cheap, remember?) and an Arduino, [Matt] is able to parse an RFID tag, look its number up in a database, and then have a computer announce "Access Denied" in a creamy "Douglas … [Read more...]