The bender isn’t without some issues though, such as that there’s no automatic method for giving it bending instructions. You can write code for the steps into an Arduino sketch, which is ...

Rather than write a bunch of stepper motor code himself, he installed and ran a four-axis fork of grbl on the Arduino, turning it into a stepper motor controller.

I like this one - a super impressive Arduino-based barometer for measuring air pressure. There's something satisfying about the link with nature, a tangible connection with outside weather.