Warning: Minor "Stranger Things" spoilers ahead.
You suspect a friend or family member has disappeared into the Upside Down and you want a word with your missing loved one. Given how unreliable the Upside Down postal service is, you're going to need an alternate communication method, but the local drugstore doesn't sell those talking lights featured in "Stranger Things."
Luckily, an Instructables user has figured out how to make a light-up alphabet wall like the one Winona Ryder strings together in the Netflix show to talk to her son trapped in a parallel dimension. "Good news. No tools are required," Instructables user bxl4662 writes. "You don't need to know how to solder or anything fancy."
You just need an Arduino Uno microcontroller, a string of programmable LEDs and a power supply. The Instructables tutorial even includes a link to the creepy font used for the project. You can print out the letters and rig them to individual lights to spell out messages like "I'm here" or "run!"
"It looks like a good beginner project for Arduino," Donald Bell notes on the latest episode of his Maker Update Web series, which tipped us off to the project. (Remember Donald? He used to work at CNET!)
Up next, hopefully: a tutorial on making your own plug-and-play Demogorgon.