This Thing Rules!
Hister
Hister is effectively a search engine for your browsing history. You install the browser extension and it quietly hoovers up websites that you visit. The best part is that it can also ingest YouTube videos! It hooks in to yt-dlp to slurp transcripts into it's index.
What that means is that I can be like "What was that video about that dude who chased a KGB agent across computer networks in the 80s?", go to Hister and search "youtube kgb" and boom. Stalking the Wily Hacker. (Fantastic talk by the way, well worth a watch!)
Riftborne
From their Steam listing: "Riftborne is a classic terminal based, real time, grand strategy game. Construct space ships. Take part in factional warfare. Hire galactic hit-men on your rivals. Raid neighbors for rare resources. Train spies to infiltrate enemy bases for key intel. Grow your empire to dominate the galaxy."
This game is just awesome! It's part idle game and part 4X strategy. In multiplayer, the game runs in real time so you can log on in the morning, queue up some actions and then log on in the evening and see that all your raids got smashed and your fleets have been scattered to the solar winds.
Great fun!
PumpkinOS
PumpkinOS is an open source reimplementation of PalmOS. I used to love my Palm Pilot. It looks like someone has ported it to esp32, so hopefully it's only a matter of time before it gets ported to an Xteink device or a Seeed Sticky or something and freaky homebrew Palm Pilots become a thing!
Sneakerweb
The main idea behind sneakerweb is that you publish your website to a .snk file, then you meet up with your friends and share your collection of websites with them and they share with you and eventually everybody ends up with these little cosy collections of websites.
I have a soft spot for this kind of impractical post collapse software. Like I know as a fairly privileged person living in Australia, I'm unlikely to ever NEED anything like this but it just tickles the prepper/homesteader part of my brain.