What you are looking for is local peer-to-peer file sharing. When I was studying, we used eMule, but that is for Windows and old. I don't have a concrete software suggestion, but looking around the gnutella protocol could be promising.
Edit: QuantumCogs suggestion is also good, the use cases are slightly different.
Oh wow. I remember trying to play this as a kid for 2 hours or so. Since then I occasionally thought about it, because the concept is interesting, but could not remember the name.
Now I can check it out again.
Honorable mention: the GNU Taler project
https://taler.net/en/index.html
Could be a better alternative to crypto.
To me the answers are useful enough and I appreciate that it understands vague questions. When I don't know enough about a topic to know what terms to punch into a search engine, I can use ChatGPT as a first step and go from there.
Maybe make it look like a spam email? :-)
Write a web server with a countdown that sends you regularly a link via email to reset the countdown.
No, basically all licenses in the family are pooled together. You own game A and B, you can play game A, someone else game B. There are 2 licenses of game A in the family, two people can play it at the same time.
That's the first thing I thought about when I saw this post. As a kid I loved the secrets in this game. I don't know if it just seems so because I'm not a child anymore but modern games don't seem to have this kind of mystery.
You could use React Native, so the language would be Javascript / Typescript.
Kitty is really popular. I'm using foot, as long a terminal has the basic functionality I need, best latency is what I care about.
https://proton.me/pass