Online javascript beautifier : Beautify, unpack or deobfuscate JavaScript and HTML, make JSON/JSONP readable, etc.
DOM Monster Bookmarklet : DOM Monster is a cross-platform, cross-browser bookmarklet that will analyze the DOM & other features of the page you're on, and give you its bill of ...
Kickstrap : Twitter's Bootstrap with themes, apps, and other enhancements
Electron : Build cross platform desktop apps with web technologies
Prettier is an opinionated code formatter. It enforces a consistent style by parsing your code and re-printing it with its own rules that take the maximum line length into account, wrapping code when necessary.