Also mandate that they're cheap, safe, can seat six, have excellent air conditioning and heating, and perform well in deep snow?

Group to Obama: regulate carbon, aim for 200-mpg cars

Raise fuel economy standards for cars, light trucks and SUVs to at least 45 miles per gallon (19 kilometers per litre) within the next 15 years, and to 200 miles per gallon (85 kilometers per litre) by 2050.