A script that adds a class to HTML when an element enters the viewport. In my case I'm triggering an animation.
I made use of this ace Plugin from Digital Fusion. http://www.teamdf.com/web/jquery-element-onscreen-visibility/194
You can view the demo here. http://function.webknit.co.uk/projects/add-class-when-in-viewport/index.html
And lots of other stuff here. http://function.webknit.co.uk/