Tildeverse
I recently joined a public unix site called Tildeverse which provides unix/linux accounts to write pages and similar things and generally exploring linux and communication tools.
I have started using a few of the features and sites including the ttm.sh image site and made a image upload command for Greenshot. The explanation how it works is here ttm.sh_greenshot.
The site I actually joined is called cosmic.voyage which is a collaborative writing site with a sci-fi theme, my ship log is at Extrasolar Outpost 037.b. I am not much of a writer, so there will probably not be long entries.
Fun fact, this site is also available on Gopher and Gemini. If your browser does not support the links, you can use a proxy: https://gopher.tildeverse.org/cosmic.voyage/ or https://proxy.vulpes.one/gemini/cosmic.voyage/. I believe the site is actually provided as a gopher service and the https and gemini versions are converted from that.
Since the site supports gopher via the public_gopher directory convention (like public_html), I created a Gopher page gopher://cosmic.voyage/1/~alexlehm/ (https://gopher.tildeverse.org/cosmic.voyage/1/~alexlehm/)
I came across the site after I started exploring SDF which has a similar approach to provide lots of communication tools old and new.