apart from the usual suspect like, Jellyfin+Plex (still have some straggler users that need to upgrade their players for JF to work properly), Immich, nextcloud etc, I really like running Birdnet-Go. I give it my CCTV camera feeds and it uses a NN to identify birds it hears.
I get statistics about species heard around the property, charts to correlate detections to seasons and weather, and some interesting info about rarer species that I didn’t know were in my area. Every morning I check it to see if there was anything new recorded.
it doesn’t really have a purpose, though the data can be submitted to larger databases, but it’s just a nice thing to have.
EDIT: Also Vaultwarden, forgot about that, super happy to be hosting my own password manager instead of trusting (and paying for) companies like Dashlane to host it like I used to.