We are – or at least, we used to be – huge fans of the Marvel cinematic universe and all the props and cosplay that it has given us over the years. One classic of the genre is Iron Man’s arc reactor — the glowing power source that sits in Tony Stark’s chest and powers his special suit. It’s almost a cosplay rite of passage to build your own arc reactor, so here’s our favourite implementation: an arc reactor that’s also an alarm clock.

As an arc reactor is basically a round, glowing thing, it should come as no surprise that Jéjé starts with an off-the-shelf NeoPixel ring, powered by a Mini ESP32. The structure that holds the electronics is printed out of black and transparent PLA, and there are ten coils of copper wire – these don’t do anything, but they do look extremely cool.

Jéjé’s provided detailed instructions for anyone who wants to make their own version, so you too can tell the time like a fictional genius billionaire playboy philanthropist.