It is a neat concept. I think I would like a more elegant solution, however, something that does not require another set of wheels, brakes, signal lights, etc. I would be cool with a drop in generator that used four mounting bolts and a aircraft style brake-away valve system to tie into a fuel tank that is in the existing car. I am not sure how good an idea it would be to drive with a near empty tank all the time until you wanted to use it. Perhaps, a bolt on tank as well? I know that would be more work than this.