I think the Adidas campaign was ingenious because it used outdoor advertising to demonstrate how consumers can make the sneakers their own. A great example of how to stimulate a brand hijack. However, I wonder if such a campaign would be permitted in the US since the company is essentially encouraging something that is illegal - graffiti.

Other companies using consumers as marketers: http://www.usatoday.com/money/advertising/2006-03-27-amateur-advertisers_x.htm

I think the campaign was ingenious too, but it worked in Germany. I believe that the same campaign in Italy would have had different drawings... Let's call it cultural boundaries.

Like you say, it is ingenious to do this but how far can this go. May we some day have an Adidas riot against a cause. Surely it is possible if the consumer grows his taste the Adidas way and takes the Brand identity truly into their hearts. I think the question is who sets the boundaries...the Brand will not claim responsibility for this disobedience, its out of their hands.