Stylo is a web app designer written in CoffeeScript and Spine. It allows you to manipulate various HTML elements, add styles and edit text.
You can find a demo here (webkit only).
The code should provide good examples of how to achieve the following:
- Element snapping, resizing and drag/drop
- Copy/paste, undo/redo & keyboard shortcuts
- Context menus and z-index ordering
- Color picker using canvas
- JSON object instance serialization
For more information, please see the blog post.