I am making an advert at the moment where the screen fills up with rugby balls using "particular 2". What I have done is use the bounce physics type to make the rugby balls stop on the floor plane. I have then had to duplicate this layer and move it up slightly so it gives the appearance that a new layer of balls is stacking up on top of the first set and so on until my screen is filled with balls that appear to be colliding with each other. (I'm pretty sure inter-particle collisions are not possible).
My question is this once all the particles have settled on the screen how can I then animate them again. I want them all to fly off the screen in different directions as an object breaks through them. I can't find any way to do this. The particles have been dispersed and have stopped and now it seems there is nothing I can do to them. If I was using the 'air' physics type this might be possible using a turbulence field but bounce gives far less options.
Unfortunately, I don't think Particular is capable of doing what you want with the bounce settings. The only way I can think of doing this is with 2 particular layers using a grid emitter perhaps. You are going to have problems lining up the balls to be exactly the same. This is really a 3d object collision shot.