How about a 60-second break from mechanical keyboards?
I made this project almost two years ago! I've only gotten to posting it now. It's a digital hourglass that lasts one minute.
The case holding all the components is printed in black PLA, while a flexible sleeve to hide the electronics is printed in black TPU.
The firmware was written in C++ using Arduino libraries, the source code for which can be found here, licensed under the MIT license.
Despite utilizing a microcontroller that has Bluetooth capabilities, no software features exist that utilize it yet. Perhaps a future upgrade where you can set the time it gives you via Bluetooth?
I had fun writing the 'falling sand' source code for it. It was especially challenging considering the grid had to be working at 45° angles. Initially, I only implemented the diagonal directions so it only fell up/down/left/right. Adding the cardinal directions was an afterthought for me.
The 3D files for the case can be found here, with no license attached. I will not provide instructions how to make one yourself. That's the fun part! (haha excuses)