This clever “Trojan Mailing” Ad campaign takes a page straight from ancient Greek war books (remember the Trojan horse?). DHL posted huge packages through its competitors, they were wrapped in temperature sensitive coating that appears black when cooled below freezing, so it was an ordinary huge black box when they pick it up.
But once it was warmed up, when pulled for delivery, it turned into the DHL bright yellow signature color with a big phrase “DHL is Faster” in front, as their rival couriers, UPS, TNT and DPD, wheeled them awkwardly around the city.
Clever! There’s no better way to advertise than getting your competition to advertise for you. And it’s cheaper than paying for classic ad campaign.