Green Light District
Once in the Green Light District consumers can get directions to participating bars using their mobile phones, interact with bus shelter ads and even find out if friends are in the area so that they can meet up.
It's a really nice promotion and great use of different outdoor media. My only grumble is that the bars tend to be the usual chain bars and completely lacking in any authenticity.
Grolsch have put together a nice video of last year's campaign: