I just started getting into embedded programming (Arduinos and Pi's) and one of the most exciting things is the possibility to make physical thing with custom buttons, toggles, and LEDs to do a thing. E.g. I prototyped a metronome (for practicing music) with an animated LED light bar (out of PVC pipe!) and pushbuttons to program it. Thing can be huge and robust, like throw-against-the-wall robust. And I like that there are only so many buttons and they don't move!
