shadcn-ui : A set of beautifully-designed, accessible components and a code distribution platform. Works with your favorite frameworks. Open Source. Open Code.
Sizzy : A tool for developing responsive websites crazy-fast.
Open sourced : https://github.com/kitze/sizzy
CSSdoc : This is a draft to bring automatic documentation to CSS files, like its known for JavaScript and PHP files through JavaDoc/DocTags.
Cufón : Cufón aims to become a worthy alternative to sIFR, which despite its merits still remains painfully tricky to set up and use.
DD_belatedPNG : better PNG background-image support in IE6
