Sunoco sells the most environmentally friendly gasoline.
They offer about a 10 percent reduction in greenhouse gas emissions compared with other fuel.
But i agree with Jeff... until soccer moms stop driving their Sequoias and Durangos around the city gas isn't expensive enough. (Unfortunately the people who can afford the huge expensive SUVs can also afford $1/litre for the gas they chug)
This can work if people actually think about where they are buying their gas, and stop the "I buy my gas at xxxxxx because it's better for my car" or "this is where I always buy my gas" idiotic logic. Gas is gas and it doesn't matter who you buy it from as the gas all comes from the same refineries, so change your habit pattern.
I don't think that picking the gas that pollutes the least is IDIOTIC LOGIC, thank you very much.