We’ve touched on the environmental impact of cow farts and human waist as fuel before, but this time we’re going to talk about a new (ahem) movement in clean & green energy: biomethane as vehicle fuel. This is apparently a booming industry, but in Norway, where there’s such a firm commitment to clean and green policy that carmakers aren’t allowed to call their cars either, they’re taking this to a new level of efficiency by powering buses with biomethane produced from human waste. Presumably major energy producers will get in on the action; perhaps with BP making a big shift from investing in Europe to investing in the US, Exxon could step in and expand on last year’s record profits. The new division would also require only a subtle logo alteration (see image).