I've been reading AutoBlogGreen for months; I dunno why it hadn't occurred to me until now to add it to the Random Blogroll. The blog covers all things automotive that relate to the ecology - hybrids, PHEVs, biodiesel, hypermiling techniques, you name it. They cover all the major auto shows, and report on a lot of sponsored competitions (like the Automotive X-Prize); they feature many photo galleries of concept cars and new releases. And on Fridays they usually post something amusingly quirky. If you like cars and you care about the environment, enjoy!