Turkish domestic appliance maker Arçelik wanted to promote its Beko energy-efficient range. Maybe with a nice print ad in one of the country’s leading newspapers? Almost, but not quite. The brand’s agency, McCann, proposed a solution that would not use a single drop of ink. It worked by changing the layout of the paper’s small ads, shifting the columns around in order to spell out the message using blank space. An energy-efficient ad, in other words.