When the Carphone Warehouse sponsored the X Factor (Europe's biggest TV singing competition) we thought it would be great to let the public star in their own ads, so we created a site where people could audition for a part in the idents by singing into their mobile phones.
After picking a song to sing, users could call a free phone number and record it. They would then get an invidual code by SMS and go to the X Factor site, where their audition is rated by the judges.
There they could also listen to other auditions, judge them and send them to their friends.
Every week we chose the best (and worst) auditions from the site and they became the ads, which then played in the live TV show. In the first few weeks we got more than a 1,800 auditions on the site and over 150,000 votes.
Watch a short video about the campaign
(judges please start here)