The evils of ethanol are fairly well-known, but apparently it may be more evil than we thought:
The widespread use of ethanol from corn could result in nearly twice the greenhouse gas emissions as the gasoline it would replace because of expected land-use changes, researchers concluded Thursday. The study challenges the rush to biofuels as a response to global warming.
Let me just note that any story you ever read that involves a mildly rigorous look at the carbon impact of doing anything simply underscores the need for a carbon tax or an auctioned permit system. Put a price on carbon, and through the Hayekian magic of market signals the aggregate carbon impact of products will be reflected in what they cost at the store. Nothing else can possibly work.