Whiskey and Coke RFID Lock Box
Good suggestion! I remember doing a quick Google search for mini RFID tags and all I found was an Adafruit one for $3/each. I didn't feel like buying one so that's why I decided to just remove it from the keychain. $1.50 for ten of these adhesive ones sounds like a great deal. Have you used these with the RC522?
Whiskey and Coke RFID Lock BoxView Instructable »