I've been thinking along these lines recently, too. What with gas prices and all...
Back in the 80's my dad took an old rear engine Renault (60s/70s?) and converted it to battery-electric. Fork lift motor with golf cart batteries, etc. The best technology available at the time. He used it to commute to work. He still has the car, but it is in very bad disrepair, not being used in roughly 20 years. I wonder what it would take to put it back into service with the diesel-electric hybrid concept? Probably too much...
Anyway, I wonder if maybe a sandrail type of buggy might be a cheaper to work with. Pull out the VW bug engine. Throw in a modern electric motor with dual shaft, put some batteries in wing compartments off the sides between the front and rear wheels. (Maybe in the nose, too, to balance out the front to back weight ratio.) Put a skin on it to make it weather tight. The Changfa/Yanmar could be mounted above the electric motor such that a belt drive could go to the other end of the electric motor.
Only thing is, I am a family of five. Where do I seat the third child? Or fourth or fifth if I'm hauling friends around?
Of course, if I could afford hub motors like mentioned above, that would be the way to go.