Arduino Technology
Build your own RFID Arduino shield

This DIY RFID sheild kit for Arduino will get you started with RFID out of the bag. The kit includes a 13.56 MHz RFID Mifare Module, 13.56 MHz PCB Antenna, and 4 x Mifare 13.56 tags which together with some basic soldering skills is a nice intro into the world of passive radio sensing.

via Tinker Blog