My homelab started out of CCIE studies, so it was originally focused on networking and virtualization. I still use it for this, e.g. running a Cisco ASAv or Vel

My homelab started out of CCIE studies, so it was originally focused on networking and virtualization. I still use it for this, e.g. running a Cisco ASAv or VeloCloud vEdge on ESXi, I've also run Xen just because I wanted to try it out. This is where I would spin up a sandbox to learn how to use something like Wireguard, or Splunk, or whatever else $dayjob or $interests prompt me to explore. But I also use my homelab to run "production" services as well: Emby/Plex/Jellyfin, Vaultwarden, a local Wikipedia, and more to come. The overkill gear let's me do handy things, like split off my IOT devices to their own SSID/VLAN with appropriate firewall rules. I can run a guest wifi network, with rolling password auth, or even no auth at all - in which case I might want to block certain web traffic and such, which I can do with my squid proxy. In summary, the answer is "whatever I want", and what I want is often to play with new (to me) tech, or practice professional skills.