I have been thinking a bit about commons and elements that work contrary to them.  Cooperative ecosystems are often polluted by by people who are ignorant of the ecosystem, out for personal gain or outright hostile  This can take the form of things like anti-competitive practices in capitalism, resource hoarding in collectivism, or general rule bending / breaking for other systems. Like a bull in a china shop, their actions can be based on their aggressive behavior or simply by their unconscious movements.

Games Theory is rife with examples of this, but so is the news every day.  So I'm starting a "bullinchinashop" tag on del.icio.us that I'd like to encourage others to use.

My goal is to come up with a shared library of real-world incidents of commons destruction - whether it is wilfull or accidental.   There are many incidents in urban planning, so you'll see examples like that in my tags.