One of the most effective street campaigns I have seen is 'Luck is everywhere' designed by Bungalow25 . Passer-bys were asked to play a simple game of the good old fruit machine; the idea was to photograph three cars of the same colour to be in for a chance to win 80,000 euros. Not only was this a brilliant way to interact with a wide audience it cost nothing to implement. A simple sign hung over one of Madrid's busiest roads publicized the casino whilst demonstrating the benefits of playing with them. Very clever.