Watch me change

Okay, it should not be that I am so easily stricken agog with wonder, but this advertisement for the Gap/GPS is way cool. I love web stuff such as this; to me, it is akin to magic. (Okay, it is Shockwave; nonetheless...)

Check it out, and then tell us what you think of the ad. And if you can explain in layman's terms how it is done, please do!