I selfhost a Writing instance. Writing is a FOSS web-based editor that supports Markdown and LaTeX. This is very minimal and fast, and you can even run it offline.
I happen to have a sizable collection of mostly Linux related books.
As an exercise in HTML, I turned an old story I wrote into a interactive game. It's still in development, so there's only a single ending so far. You can play it here.
I used meesaltena's
to make an SSH heatmap of failed login attempts. It refreshes every hour. I've moved on to public key authentication and disabled password log in so it's empty
right now, but I don't feel like taking it down just yet.
You can take a look here.