I've created [jQuery Terminal][0] in about 2010 I think it was first library that allow to create CLI applications in Browser. I've started it because I wanted to have SSH like experience on my shared hosting that didn't provide SSH access. I've build application using my Terminal, called [Leash][1]. I don't use it anymore because my current shared hosting have SSH.
I've also build [sysend.js][2] (random name with send at the end). It's for sending messages between Open Tabs, It have nice API and it works in all modern browsers and even some older ones like IE11. I didn't know any existing library that did the same, that's why I've created one.
Another library of mine is [Tagger][3], because there where no Vanilla JavaScript library like this. I needed it for StackOverflow Q&A site that I've started, but abandoned and it was inspired by StackOverflow tag editor.
Yet another library is [LIPS][4], Powerful Scheme based lisp in JavaScript. LIPS is acronym LIPS Is Pretty Simple (at least it was when I started the project on [Codepen][5]). It started as lisp in JavaScript, but later I decided that I want fully working Scheme (compliant with R5RS and R7RS). I'm still working on Beta 1.0 version, that is like completely new project. I'm also still working on new website that will showcase beta version better.
I've also created [Favloader][7] - favicon animation library. [LILY][8] - Zero dependency, simple version of YARGS for parsing command line arguments.
[0]: https://terminal.jcubic.pl/
[1]: https://leash.jcubic.pl/
[2]: https://github.com/jcubic/sysend.js
[3]: https://github.com/jcubic/tagger
[4]: https://github.com/jcubic/lips
[5]: https://codepen.io/jcubic/pen/gvvzdp
[6]: https://lips.js.org/
[7]: https://github.com/jcubic/favloader
[8]: https://github.com/jcubic/lily