Mjolnir

Thor's Hammer (yep, actual magic hammer here)

Magic (also known as strong electromagnets, some control circuitry, and an RFID sensor) will allow only the worthy to pick up this hammer. The primary objective is getting the hammer itself functioning, but we would like to embed the RFID chip inside a bracelet or watch to make the trickery more subtle if we have time. Inspired by a love of comics and superhero movies and this guy: https://www.youtube.com/watch?v=0_8Xhzt5YQI