At work I've only ever used various distributions of Linux, but at home I've started using OpenBSD and FreeBSD. I'm currently running FreeBSD 12 on my long in the tooth HP Microserver N54L, with a ZFS mirror + NFS/Samba serving up music/photos to my home network. It's been rock solid for the past few years, and I love in particular how 'boring' it is. It has great tech like ZFS but it's very predictable.