GEM: The Global Environment Monitoring unit is a European commission that makes up on of six units in IES: The Institute for Environment and Sustainability. The IES is a group of scientists (about 65 according to their about page) that are devoted to making sure development in Europe and the world is done is such a way that it doesn't cause problems. Today I stumbled upon a project they did called, "Travel time to major cities: A global map of Accessibility" and boy isn't it beautiful? Click on it for a much larger version, and click though to the project for information about what it means and what it doesn't.