EtherPad : Etherpad is an Open Source online editor providing collaborative editing in really real-time powered by Node.js
Mockingbird : Mockingbird is an online tool that makes it easy for you to create, link together, preview, and share mockups of your website or application.
Feed43 : Your favorite site doesn't provide news feeds?
This free online service converts any web page to an RSS feed on the fly.
