A fascinating phenomenon that presents itself when you cough, sneeze, wheeze or in some form manage to transfer drops of transparent fluid to a CRT (aka, a monitor).
The drop flattens itself on the screen and turns into a plane-convex lens, a miniature and very perishable magnifier that allows you to see the individual phosphors in the screen.
The net effect is a round point with brilliant primary colors: a lenticular spit rainbow.

This node is mostly so that you realize that you are not alone, and you are not hallucinating.