One interesting thing about the way that technology has brought us together is that we have more of an opportunity than ever to build our own worlds of sorts. This can exist in the form of an indie video game for those with the programming know how, or even a Dungeons & Dragons campaign that you decide the general atmosphere of.
And when such an opportunity presents itself, we can get engrossed enough in the act of creating it that we start throwing in little details that were largely made to amuse ourselves, but can also serve as surprise rewards to the people looking closely enough to discover them. These surprises are known as "Easter eggs."
And as we're about to see, it turns out that you don't have to create your own world to make these Easter eggs. It turns out that they can be just as fun to hide in real life.