And would using white squares of solid colors as sprites not be an exception? What I'm trying to do is create a sort of "matrix" of squares of various shades of grey which blink in and out of existence in a spherical formation, and parent the system to the player, so that it looks like an animated skybox. I also want full coverage of the sphere surrounding the player. The idea is that the player is trapped inside a tv screen showing only analog noise. Brilliant, I know. Seems pretty graphically simplistic but maybe it would be to hard on memory simply because of the amount of particles? It's not like the particles will be one pixel in size; more like 8x8.
I realize that Source wasn't particularly designed for this kind of effect but any ideas as to how to approach it, using particles or otherwise, are appreciated.