Maintained by author J.H. Crawford, carfree.com is perhaps the most thorough and well documented website on the subject of living without automobiles. It contains tremendous amount of links, and articles on everything from urban planning to package delivery.

The Sierra Club Challenge to Sprawl Campaign site gives an in-depth examination of the negative effects of urban-sprawl, and offers noteworthy solutions.

This is the EPA's site about acid rain. It details where acid rain comes from, what it does, and why it’s a problem we need to solve.

Adbusters site on Reclaiming Urban Space is total quality. It’s just one of their many campaigns and well worth a visit.

The Detroit Project is a grassroots campaign co-founded by columnist Arianna Huffington. The site has great facts and statistics about SUVs, and a lot of information about the SUV-terrorism connection. You can also watch a couple of fantastic anti-SUV ads on the site (which require RealPlayer).

The next time you’re at the bookstore, check out these two great books about car culture: Asphalt Nation: How the Automobile Took Over America, and How We Can Take It Back by Jane Holtz Kay, and High & Mighty: SUVs – The World’s Dangerous Vehicles and How They Got That Way by Keith Bradsher.