I'm fan of #garage !
It's a distributed object storage service #S3 tailored for self-hosting.
It runs on old PCs. It's build to be resilient with geographical redundancy.
They released a new version 3 weeks ago: https://git.deuxfleurs.fr/Deuxfleurs/garage/releases
Gitea: git with a cup of coffeegarageS3-compatible object store for small self-hosted geo-distributed deployments