hiho, basically box2d-jquery is a jquery wrapper around box2dweb, it's quite simple to use
$("#some_element").box2d({'y-velocity':10});
it was fun to code, basically it
* creates absolute positioned clones of your selected elements https://gist.github.com/4051578
* and animates them usind CSS3 transforms / translate / rotate
* the values are calculated using box2dweb
i created it as i sponsor a javascript/jquery conference in my hometown (we need more dev-conferences here) and wanted to create something cool.
please fork it on github (zlib license) https://github.com/franzenzenhofer/box2d-jquery
update: more examples linked from github Readme.md