To userp the Green Lantern oath is a sacrilege. But calm your rage as you take in this Green Lantern battery and ring project. [Jon] built the power battery portion out of LEGO, but inside you’ll find an added bonus. An Arduino uses a set of LEDs and an RFID reader to bring the object alive. A matching ring contains the RFID tag that activates the lights when held up to the lantern’s lens. You can see this used to charge the power ring (and join in by saying the oath) in the video after the break.
Want to build something like this but don’t have an RFID reader? This would be easy to pull off by adding a magnet to the ring and a hall effect sensor in the lantern. Maybe this will make you rethink your Halloween costume this year.