CodePen - A front end web development playground.
MIT License - A license from the Massachusetts Institute of Technology.
JSFiddle - Test your JavaScript, CSS, HTML or CoffeeScript online with JSFiddle code editor.
Simplified BSD License - Also known as the "2-clause" BSD license, this is a simplified version of an open source license created at the University of California Berkley.
JS Bin - Sample of the bin:
GPLv2 - Created for the GNU project, the GNU General Public License version 2 is the most popular free software license.