It's something I've been planning to do since the movie came out, but my only reference right now is a tiny animated gif someone posted on another site.
Here's a rough draft that I did this morning. It still doesn't have the right particle shape, and a final effect would probably require alot more particles, but it may give you some ideas.
http://pi.shockingtales.com/iels/nightcrawler01.zip
When the DVD comes out here in another 2 weeks, I'll probably be able to get something a little more convincing from watching it over a couple of times.
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Elvis Deane!
The particleIllusion FAQ
particleIllusion Resources and tutorial CD
Astounding Adventures
