My all-time favorite (so far) was running our company email server on a Mac SE/30. Although that might not qualify as low-end, it was a machine our department got at no charge when the donor upgraded. Good times, an elegant weapon for a more civilized age.

I currently use an HP Stream 11 Pro that I got for not quite $100. I was going to run Linux on it, but the trackpad was unusable for me without lots of tuning of low-level parameters. It is usable as a dev box for static HTML sites, using VS Code on Windows 10, even non-GUI WSL2 Linux basics. 4GB of RAM, 6 Watts of heat.

Windows is a huge amount of work for me, but learning PowerShell or Python doesn't require a ThreadRipper. Or 1080p video.