The absent-minded professor There are three variants of procrastination, depending on what you do instead of working on something: you could work on (a) nothing, (b) something less important, or (c) something more important. That last type, I'd argue, is good procrastination. That's the "absent-minded professor," who forgets to shave, or eat, or even perhaps look where he's going while he's thinking about some interesting question. His mind is absent from the everyday world because it's hard at work in another. Paul Graham, Good and bad procrastination procrastinationproductivity
Truchet Tiles Truchet tiles are square tiles decorated with patterns that are not rotationally symmetric. When placed in a square tiling of the plane, they can form varied patterns, and the orientation of each tile can be used to visualize information associated with the tile's position within the tiling. Wikipedia en.wikipedia.org The Tiling Patterns of Sebastien Truchet and the Topology of Structural HierarchyWang tiles graphicsart