I run a Proxmox cluster with 2x Dreamquest pro, each with 2x10TB had in an IcyBox, plus an external Raspberry Pie with a 12 TB disk for backup.
The disks are refurbished to keep the costs down but run in a mirror setup. So if one fails, I’m fine. I use an old laptop as a 3rd node and the main nodes replicate their load, so I‘m fine even when one node is dead.
My old Samsung printer can enter a state where it consumes ~100W without doing anything meaningful. It’s not obvious what is wrong, but without power monitoring I would have never realized this.
CO2 levels raise astonishingly fast when people are present in a room.
I have mice visiting my garage and I can tell when by looking at the motion sensor history.
My uninsulated roof stays frost free even at -15°C.