This is the Box2DFlash demo, using Jangaroo to run without Flash.
If you have turned off Flash or no Flash available (e.g. on iPhone), the original Web-site says:
You need Flash to view this content.
Box2DFlash is an actionscript library, do you really think you could avoid Flash on the website?
Actually, yes. It is possible!
Above, you see the original Box2DFlash framework and example code recompiled with Jangaroo AS3 to JS compiler, using a Jangaroo Flash API re-implementation, which implements Flash drawing using HTML5 canvas. This means it runs in every modern browser (for Microsoft Internet Explorer, you need version 9). For best performance, use Google Chrome 5 or IE 9. Safari 5 is also fast, but stops every other second (garbage collection?). Safari mobile (iPhone, iPad, iPod) works, but the demos do not yet support touch events, so only the falling 'Ragdolls' can be viewed. Firefox 3.6 is slower than Chrome, but steady. Opera 10 flickers and pops up the JavaScript console with strange exceptions.
The button on the right-hand side loads the original Flash version of the demo (and of course only works if you have a Flash-enabled browser).
Demo Instructions: Click and drag to manipulate items in the 2D world. To use the keys to step to another demo, you have to focus (click) into the corresponding demo version (Jangaroo left, Flash right) first.