I've got an aging Dell Optiplex microsff running OPNSense as a router on a stick, handling the house LAN. Then a HP Prodesk mini that runs containers on top of Rocky 9.
Free oracle ampere instance running Synapse and Onlyoffice DS for my Nextcloud instance, and Adguard Home (DoT&DoH) to block ads on the go. Not really homelab stuff, but relates closely... Probably going to set up a Lemmy instance on that one too, seems worth it if ARM is not an issue.
Going to try making a RPi 4B 8GiB + FreeBSD + 2 HDD ZFS mirror "NAS", though it's main usage is going to be local backups, mostly just sitting idle. Finding a powered 2-disk USB3-SATA disk housing that stops the disks properly (not with emergency head retract) has been surprisingly difficult. If anyone has suggestions for one, I'd be grateful. Probably going to have to write scripts to issue hdparm commands automatically when necessary.