Audiobookshelf - Self-hosted Audible. I cannot believe how smooth this is. I set up the docker container, tweaked the ID3 tags on my audiobooks (to group series), and that was it. The Android app is listed as alpha, but it has been nearly flawless for me. I am astonished.
Tailscale - A slick low-config VPN solution. Probably everybody knew about this except for me, but I recently tried it and it's great. I had to tweak several things to fit my exact setup, but once I figured it out, it has been exactly what I hoped for. No more messing with dynamic DNS or opening ports. I just start the client and I'm home. I'm hoping I'll have some extra time soon, and if so I'll try to go full FOSS and attempt to use Headscale on a VPS.
headscale definitely makes running a home lab fun again.