This clever ad for a Philippines airline only shows up when it's raining because it was made using water-repellent spray. In an effort to advertise flights to their native country, Cebu Airlines launched an ad campaign created by Ogilvy Asia. If it's not raining out, the unique QR code and copy reading 'It's Sunny in the Philippines' is hidden from view.
The water-repellent spray was painted onto the busy streets of Hong Kong using a stencil. When it began to rain and the ad and QR code became visible, people in Hong Kong could scan it with their smartphones and receive information on discounted flights. As a result, Cebu Pacific flight bookings to the Philippines increased by an impressive 37%.