) as soon as I saw it, but even in the most simple test I really encountered like a little pain have to deal with that layer creation/splitting process aaall the time, so... for curiosity & laziness (I wonder which of this two human nature forces will be stronger) I've just started to implement this functionality that I had never thought be so easy to do! 
As you probably still imagine (although I'm not totally sure if "splitter" will be the better word to describe it, the tool creates a new layer for each shape as you go freely painting here and there, so if you are inside a group with Physics activated (or you put'em inside it later), you'll see how each one of they come to "life" and individually reacts as soon as you press play, is that simple!
So I don't know why so much text 
Of course the best thing of use the Scatter Brush for this, is you get all his advantages at once! Like shape/color variations, pen pressure (where available), freely tracing and, of course, the possibility of use your own clipboarded objects, thanks to all that, it practically becomes into a new physicable Particle engine
...Plus! With the new layer management possibilities, you can select all of them (that surely won't be a few), and delete, move, etc in a jiffy, THANKS Ra! Well, I hope you like it! And although It's a very rough/young version, I think that you can overwrite the original one (previous backup just in case, of course...) without any problem, or I hope so... Here it is the thing!:
lm_scatterbrush.zip...Enjoy!
Ramón López.
), I think.
