There is an interesting book out there called the Oregon Experiment. In this story, an architect got the task to design the campus of a university. But, he didn't approach it as expected. The first thing he did was to order some bulldozers to clear the whole campus area between the new buildings. Then, he seeded grass everywhere and… waited. After some months, the grass grew and the students started walking their preferred ways. This resulted in an interesting pattern of emerging trails. Some of them were very small; some were bigger because a bigger crowd seemed to use them constantly. See the figure with the trails for an impression. The following image shows this. With this highly valuable information, the architect knew where to build the best and most effective ways because the people who use the...