#5: Tape So Strong It Holds the Billboard Together
There is no mystery about what this 3M ad wants people to believe. A giant roll of tape appears to be holding the billboard in place, wrapped around the corner like it saved the whole structure from falling apart. It is simple, oversized, and immediately understandable from the road.

The fun comes from how casually impossible it looks. Of course tape is not really supposed to hold up a billboard, but the image makes the product claim feel instantly clear: this stuff sticks. It is the kind of ad that turns one basic feature into a full visual joke.
