"It's what makes time travel possible, Marty." This was another "I've always wanted one". It was also a great excuse to teach myself to work with the Arduino platform.
My flux is built from the same Stahlin electrical box used in the film. The inner-workings are hand-made to replicate the impossible-to-find original relays. Specifically, the fluxing tubes were made from acrylic test tubes, the flux bases are resin casts.
The fun was getting the electronics to mimic the "fluxing" seen in the film. The system is powered by an Arduino microcomputer. The wiring of the LEDs was pretty straightforward, but the fluxing meant some Arduino learning for me to get the iconic "fluxing" look right.