Light graffiti in AE

I first saw "light graffiti" posted by PIPS:lab as a Shockwave site. After graf experiments flowered further Wired did an article, and now Apple has a cool iPod commercial.

Andrew Kramer shows you a similar technique in AE with Trapcode Particular at Creative Cow.

Update: newer posts on these topics can be found under the tags graffiti, and light.