This person deserves a lot of kudos irrespective of HN finding his work "necessary" OR "worthy". There is a joy in solving a problem (scratch an itch) for the sake of it.
You can live the exact life you dreamt of as a kid with a $150 3D printer and $100 in various Arduino parts. The hard part is imagination and time, everything else is very easy. I would really encourage you to get into making things, it's extremely gratifying.
Here's a random thing I made last night, and the reason why I slept at 8 am:
EDIT: I was half expecting links to printer and arduino parts but coffee offer still stands because you just gave me my "duh!" moment.
I'll post the links to the CAD files and code shortly, I just need to find a name for the thing first.
EDIT: I found a name! I call it "The Timeframe". As promised, the code: https://gitlab.com/stavros/the-timeframe