You can also see the result on the video below. For the rendered animation I've pulled the camera a bit further back and I've also increase the force field to -350 (from -300). As always you're free to experiment with materials, lights etc. You could try cycles for rendering and add some more objects -some cubes for example- for different object collisions/interactions. Play with the force too and see how differnent types of forces affect the objects animations. Now that everything happens in the viewport (and baking through the BGE isn't required) you got no excuses; experiment!
As always the final .blend file is available to download through Blendswap. Get it from here.