American Express is the latest to take the lead in transforming consumers from passive bystanders into active participants. The 15 Second Clips site invites everyday people to upload a 15 second video clip that's entered into a competition co-sponsored by the Tribeca Film Festival. The site experience is on brand, executed well—and the gallery allows you to view previous submissions. And of course you can e-mail and even subscribe to an RSS feed of the latest clip submissions. Nice example of engaging your customer, then allowing them to become part of a digital conversation facilitated by the brand.