I've thought about getting the next generation of Smart car with an electric motor for local journeys, but then the electricity bills will spiral, so if I invest in a wind turbine and\or solar panels for my house I could be close to self sufficient in motoring terms, albeit with a hefty upfront investment. I would also have to hide a small petrol sports car away in the garage for high days & holidays!
But then today I hear of a car that runs on hot air (honest!), all I need to do now is find a wife who can power it!!
Link to BBC News website with video of car & designer is here.