[aplc0r]

Here is one from 1958 in Japan that has been preserved. The whole video is worth watching, but here is a demo of a running calculation: https://youtu.be/_j544ELauus?t=1027.

[eigenvalue]

One of my favorite YouTube channels. Marc has tons of amazing vintage computer content. The Apollo guidance computer series in particular is great.

[fathyb]

That was a great watch, thanks for sharing!