Today I’d like to share a half-baked idea for a programming exercise. But first, some context:

One day in a high-school art class, our teacher announced that we would be painting a still life. He placed a jumble of random objects in the middle of the classroom and asked us to set up our easels in a circle around it, facing inwards. We began to paint, but after five minutes he stopped us and asked us all to put down our brushes, move to the next easel around the circle, and continue painting right where the previous student had left off. Five minutes later, up and around again. We continued this pattern for an hour, and when the class ended we had a dozen truly collaborative paintings of the scene; each student had contributed to every painting. Neat, right?