Ask HN: Most interesting tech you built for just yourself?

My family has historically been very into genealogy research, so we've got lots of family tree info. I've been working with my aunt to put together a webapp to create/edit info, see relationships, show ancestors/descendants of individuals. We've also started adding photos recently, which is really cool.

Favorite feature we've built: "are you my cousin", where you choose 2 people in our database and it calculates how they are related. First time I got to write a search function outside of a classroom!

I'm sure Ancestry does all this and more, but it's nice to have something that we built that's just for our family. We also use it all the time to verify relationships/birthdays!

> div.innerHTML = xhr.responseText;

Did you test this? Because CORS aside, that sure does look like it will append the whole of page 2 to the body of page 1 and get progressively worse as one reaches the pagination of page 2. It would be more code (and memory pressure) but I believe the correct impl of any such trickery would be to reach into the actual table of page 2 and jam that into the body of page 1

About a year ago I got a Tesla K80 off eBay for about $200. It's basically 2 Tesla K20Xes in one card, so it's pretty powerful, but the downside is that it's a datacenter GPU - it doesn't have any cooling.

I 3D printed a fan shroud for it and put an old (but surprisingly powerful) fan on there, and that worked ok. The issue, though, was that I wanted the fan to be quiet when the GPU was idle, and I couldn't figure out fan control on Linux, so I decided to control the fan speed via an Arduino.

I took a spare Arduino, some wiring, and despite never before programming anything for Arduino, I managed to hack this together: https://github.com/askiiart/k80-linux-cooling

It takes the GPU temperature, turns that into desired fan speed, then sends the desired speed to the Arduino over USB. The Arduino just controls the fan speed via PWM.

As a color-blind person, most of the time when stuff on screen was only differentiated by color (like red/green status indicators), the go-to-tool would be the system’s digital colorimeter for me.

It was tiresome to have to launch an extra application and inspect RGB percentages to derive what color I was supposed to see.

The colorimeter I made activates while holding down an inconsequential modifier key on the keyboard and shows the name of the color.

Now I can also quickly double-press that modifier key and copy the color value to the clipboard.

Holy shit. This should be mandatory practice, government funded for any court related phone visitation.