McDonald’s and advertising company Leo Burnett recently engaged in a unique digital billboard campaign across 10 cities in the UK. The campaign – which also featured the work of Grand Visual (a New York City-based production company) and OpenLoop (a digital out-of-home campaign manager) – targeted highway drivers during rush hour. According to Adweek, the billboards spotlighted Big Macs during light traffic, but once road congestion increased, the imaging shifted to a McDonald’s logo and message, “Stuck in a jam? There’s light at the end of the tunnel.” Grand Visual told Adweek that longer copy that runs during heavy traffic delivers “a relevant and powerful call to action.”