How do you make a Hummer, the most aggressively anti-environment vehicle ever made, eco-friendly? Have it pulled by horses!
That's what Jeremy Dead did by converting a Hummer into a stagecoach and having two white horses (named Duke and Diesel, naturally) pull it around Central Park in NYC. Sure, it might not have had the pickup of a traditional Hummer, but it also didn't burn a bigger hole in the ozone layer as it was driving. So overall, I'd say it's an improvement.