2D physics engine

I want to simulate some basic physics to a scene that consists of a top view camera looking at the top of a desk which has some items on it (mostly primitive shapes). I would need:

  • scene bounding
  • collision detection
  • dragging and pulling physics of objects (not just simple startDrag())
  • friction and bounce (2D)
  • no gravity necessary, because of the top view

Most of the engines that I’ve googled have some of that, but they don’t have the dragging of rigid bodies. I found just one (Box2DFlashAS3_2.0.1) that would be great, but there’s practically no documentation or tutorials for it, so it’s hard to make something on my own.