Aerodynamics in motorsports is one of my favorite subjects.

Back in the mid-2000s, NASCAR was essentially running the sideways profile of a wing as a car.

In the photo, you'll notice that Dale Earnhardt Jr.'s "Bud" sticker is raised or 3D. This was not just a promotional exercise but actually driven by aerodynamics.

The camera that this photo is from stuck up 6 inches or so from the roof of the car. This caused "drag" which would make the car slower as it raced through the air. 

To combat the drag, the team figured out that if they stacked stickers on top of each other like shown, it would reduce the amount of drag by directing the air above the camera more efficiently. 

Ultimately, this small little trick produced more speed resulting in many wins for the Dale Earnhardt Jr. team at "drafting" tracks such as Daytona and Talladega.