If you’re big into board games or tabletop role-playing games like Dungeons & Dragons, you’ve probably got several dozen dice scattered around your home. Those come in all sorts of sizes, from the classic 6-sided dice in a Yahtzee! game to the almighty D20. You’ve probably also lost at least a few of them. You could use one of those smartphone dice apps to replace them, or you could build Paul Klinger’s Compact Universal Electronic Dice.
This is a small electronic device that’s just barely bigger than a standard 6-sided dice. It can emulate anything from a 2-sided dice to a 63-sided dice, so it’s suitable for just about every game ever made. It has just two buttons, a knob, and six LEDs to display the dice in binary. Holding the left button rolls the dice and releasing it shows the roll. To change how many sides the dice has, you just hold down the right button and twist the knob.
Klinger designed the Compact Universal Electronic Dice over several iterations, and the final version uses a custom PCB mounted in a 3D-printed enclosure. It’s controlled by an ATtiny1614, and powered by a single CR2032 lithium battery. Klinger doesn’t have any plans to sell these dice — production and fulfillment just wouldn’t be worth the effort. But, he has graciously provided the design files on GitHub, so you can make your own!