Grey's Global CCO at the time, Tor Myrhen, asked me to represent Grey in the Instagram Creative Hackathon. The assignment was simple: use the platform in a way that's never been done before.
I got to hand-pick a small team and choose any of Grey's clients. We chose Volvo, which had very poor unaided awareness among the "urban rebels" for whom the XC90 was built. Our hack was to stop thumbs by giving them a role--we made the thumb the car. We presented to the Facebook Creative Council along with teams from about 10 other agencies. Technically, it wasn't a competition, but come on.
We wound up selling the idea to the client and producing the campaign. Facebook and Instagram still use the campaign in their case studies on how to optimize creative for the platform.