I create particle demo build with Papervision3D for the technical book of wonderfl. BitmapEffectLayer is effective for drawing particles.
And I posted demo & source code at wonderfl (here).
I create flash demo with Papervision3D and Stardust – as3 particle engine. Stardust supports 2D and 3D and easy to extend.
Three demo of learning is posted at wonderfl. Source code and demo is here.