Here is a video I really like. You can see air traffic around the globe and in some way, this feels really organic to me.
Planes are like ants trying to find food and auto-organizing themselves (not necessarily with the shortest path). This recall me of the Ant colony optimization for solving TSP problem.
Here are some resources for the ACO optimization for TSP problems: http://www.scribd.com/doc/3689188/Ant-Colony-TSP-Optimization, http://www.ugosweb.com/Documents/jacs.aspx or http://www.idsia.ch/~luca/acs-bio97.pdf.
