Deadline Couriers created an effective PR stunt by building a billboard message that included a 8 day countdown timer. At the end of the 8 days it literally blew up.
I just love the way the message ties to the service offered by the brand !

ChallengeOptimus is a mobile phone company based in Portugal wanting to target young people within a big music festival.  So they came up with a plan to create a unique viewing platform service provided by ten big men.  The service called "broad shoulders" was greatly accepted by the young people in the festival and word quickly spread across the festival.  More people used the "Broad Shoulders" service to get a better view of the concert, search for a lost friend in the crowd.

Why did this work ?
The "Broad Shoulders" service was unique, free, fun, and provided a benefit to people.  It’s no wonder word quickly spread about the service across the festival and ChallengeOptimus’s brand health would have received a boost in the process.

So when you are thinking of reaching a particular audience, think of providing something that is unique and of such benefit that your audience can’t help but spread the word.