Ask HN: What's the coolest physical thing you've made?

Not a huge deal, but I created an Arc Reactor using micropython and neopixels! https://www.afox.dev/posts/arc-reactor

Piano stand from grey oak wood

Funny, I was building fiber optic switches around 2010-ish. I'm not talking one of those cute little 48 or 64 port things. I'm talking 250+ inputs and 250+ outputs, where each input is able to route to any output port independently, all with under IIRC, these things were like 18U beasts. I think 4 of them fit on a standard rack? One of the reasons we employed interns was so we'd have people to plug the damn things into the calibration and diagnostic rigs if necessary. Think about it: each LC connector has to be cleaned, then plugged into the correct port, for over 500 ports. If cleaning and plugging in the connector takes, say, 2 seconds in total, that's 30 minutes just to get it hooked up to get checked out.

Besides getting to play with high powered lasers and work on exotic hardware pretty much nobody has ever seen (which also sold for more than my annual salary at the time), I frequently got to work in one of our clean rooms (my sinuses loved me at that job lol), work with hardware and mechanical engineers, and usually had to figure things out on my own, because nobody else was building these things at that scale and there were no fine manuals to read.

Fun times.

SmartPoi, the Android WiFi controlled Persistence-Of-Vision LED equipment I use in my flashy light juggling shows every week.

When I bought my remote controlled juggling equipment I thought I had everything, then I found out about Pixel Poi(TM) - which at the time were unobtainable for the kind of budget I was on. I actaully cried. For real.

Video that made me cry -> https://www.youtube.com/watch?v=RWeUQowxVlM - the good stuff starts about halfway.

I knew I had to have them, so this set me on a 10 year journey over 5 prototypes (including an early one on stripboard with 120 hand soldered LED's!) where I taught myself to program, 3d CAD, design circuit boards - even did a full Stanford U course on networking. It gave me the skills to survive the pandemic financially by making a living doing remote coding jobs (I'm a professional juggler and magician).

The project lives on today in my show and in the future at http://magicpoi.circusscientist.com - where I am bulding it out to be a full platform for IOT flashy light equipment.

I used to made of ritual black candles