I ordered a backissue of Particle Illusion a while ago and have now tried the program and I can really recommed it for particle effects. It creates 2D images and animations. As an example you could use it for smooke, cosmic clouds, fire ,comets etc. As you can render out with an alpha channel you would be able to use the effect in post render/editing and depending on the possibilities in you renderapplication. In Vue just put the render on an Alpha plane and place it in your scene. It would come in handy for ordinary 2D paintings as well when you want an explosion, commet trail etc. I did however find a little bug (at least I think it is one). In order to render out with transparency (alpha) channel you must save in Targa format but it does not appear in the dropdown of selectable file formats. It was however no problem as just typing it in as in example 'myimagename.tga' worked just as well. There is loads of extra effects to download at there site and you can create you own to. I can really recomend this one. I post a picture later.