Its not quite low end but I use a T480 with ubuntu as a home server for plex etc.

I set it up to boot from the ACPI signal and run with lid closed so it boots from the wall switch.

"Not quite" is an understatement, that's a nearly brand new premium laptop. Isn't it a shocking waste to use such a thing for a server, and not - say - a Raspberry Pi 4? Like using a Porsche as a standing generator.

I actually used a raspberry Pi for a while as a Plex server but it's underpowered for transcoding.

I dont use that laptop at all these days so I put it to use there.