I like watching the shadows move during a sunset. I don't know if you've ever noticed, but they start to move really fast as the sun sinks lower and lower on the horizon. Usually, such a past-time would be relegated to the ranks of paint drying or grass growing. But at sunset, that's when things really get interesting. Sometimes if there's a shadow moving across a chalkboard or whiteboard, I like to mark it and then see how long it takes to move a foot.