I have an older house and cold cellars are common here. It's a room outside of the foundation in the basement and the roof is the floor of my porch. It was originally intended to keep preserved food cold passively.
So I threw a 32 core xeon server in there. It's isolated enough that the fan noise doesn't carry, and nothing I can do will make the core temps go over 28C. Free cooling during the summer, and in the winter, waste heat from the server helps keep the cold from leeching into the rest of the basement. It's really a beautiful solution.
The server itself runs proxmox, and I've got four or five services exposed to the internet behind an nginx proxy. Most of the time I don't ever have to touch it.
The -only- thing I don't host at home is my email server. Mostly because it's very old and I don't want to upset it, but also email behind a residential IP can be painful.
Everything I host is just for my personal use, and it's been a pretty worthwhile experience. It doesn't take too much of my time, I get to learn new skills, and at the end of it, I get a service I was going to use anyway, but I have absolute certainty that my data is under my control and no one else need be involved. It's nice.
I still need to figure out long term backups, but for now I periodically dump to an external drive and store it in a fireproof safe in the same room. That's as secure as I can get in this environment and I think it's good enough.