Honda has it... the Civic GX has been rated by the EPA as having the cleanest burning internal combustion engine in the world, with exhaust that is cleaner than even the air you breathe. The Civic GX is fueled by compressed natural gas (CNG) and is certified as a Super-Ultra-Low-Emissions Vehicle (SULEV) by the California Air Resources Board (CARB). http://www.ngv.org/ngv/ngvorg01.nsf/bytitle/HondaCivicGX.htm The Honda Civic GX is sold in the USA, along with home refuelling appliances, which tap natural gas lines, compress & store it in your garage to refuel your CNG vehicle. The home refuelling appliance is manufactured here in Toronto by Fuelmaker Corporation, which has been in the industrial CNG business for over a decade. http://www.fuelmaker.com Fuelmaker Corporation hopes to augment its CNG refuelling appliance with both reformers and electrolyzers, so that in the future compressed hydrogen can be obtained from multiple sources. This diversification of fuel sources would include water, natural gas, propane, methanol, and even gasoline. The cost of Fuelmaker's home refuelling appliance will be approximately $1,500 at annual production levels of 20,000 units or more. Their home refuelling appliance is poised to facilitate the future hydrogen economy. Today, it is already enabling the introduction of ultra-clean CNG-fueled cars, such as the Honda Civic GX.