Sense 1 sight

I was sitting at work the other day. I usually sit by the window so I can entertain myself by looking outside. I watch cars and people go by and watch the weather or whatever is going on outside. It's less boring than my job. This day I had to close the blinds because it was bright out but I found out that this gave me a much more interesting way to watch the cars. The blinds are your typical horizontal office blinds. The were rotated upwards so any light that got in went up instead of down into your eyes. I happened to look up and notice the light was cast on the ceiling and part of the adjacent wall. Suddenly the rows of light started to move and ripple. Brighter beams of light would travel up the fainter rows of light that were already being cast on the ceiling. I would see this intermittently sometimes in one direction instead of another or both at once. I also noticed other beams of light coming through vertically where the blinds and the vertical edge of the window met. It all combined to make something very close to a laser light show projected on the office ceiling. It took me a minute to realize that the movement of the beams of light was the sun bouncing off of the tops cars that pass by and bouncing back up and between the blinds. I was watching the cars but indirectly. They made these bizarrely rhythmic patterns of light on the ceiling that were much more interesting than just watching the cars go by.