CodePen - A front end web development playground.
Eventbrite - Discover Great Events or Create Your Own & Sell Tickets
JSFiddle - Test your JavaScript, CSS, HTML or CoffeeScript online with JSFiddle code editor.
Eventzilla - Eventzilla lets you sell tickets online and manage attendees from one integrated application.
JS Bin - Sample of the bin:
Splash - Anyone can create a Splash event, whether you're a company hosting a single event or an individual hosting a personal event like a birthday or wedding. Get Started for Free. Text goes here. X. Full Event Program.