Two years ago, An Inconvenient Truth was surprisingly well-received at the Sundance Film Festival. This year another environmental doc, Fields of Fuel, turned out to be a huge hit with audiences, winning the audience award last night for documentary. Directed by environmental activist Josh Tickell, Fields of Fuel is a film about biodiesel -- fuel made from organic products. It can be made from corn or soybeans, but can also be made from agricultural product less impactful on the environment, like switch grass and algae.

Tickell lays out the case for biodiesel as the fastest and most sustainable means to reduce our country's dependence on oil: Henry Ford and Rudolf Diesel both designed their engines to operate on vegetable oil, but the increasing dominance of the oil barons, in particular John D. Rockefeller, says Tickell, killed biodiesel before it had a chance to get off the ground, laying the framework for the oil dependence that drives everything from home heating to how we get around.