Diary: Name that Tube

Outdoor media owners often try new ways to get the public and wider industry to engage in the medium.

Diary thinks CBS Outdoor has come up with a rather nice way of doing just that with its "Look for Longer" ads. Two weeks ago, ads with an array of cryptic images started appearing on CBS Outdoor sites on the London Underground. It turns out the ads are from CBS Outdoor itself and each of the images stands for one of the 75 Tube stops. There are prizes up for grabs for people who are able to decode the images and, judging by the hashtag #lookforlonger on Twitter, London's awash with skiving workers trying to figure them out.