Thanks for the link to this,Brian.
This subject is one of my interests too.
It seems to me that lightweight,physically small,highly economical personal transport is the way to go rather than the large hybrid and electric vehicles which are being promoted.
An inspiring project - but don't forget its measured in US gallons that are bigger (20oz per US pint, 16oz per UK pint, so 177mpg in the UK)
I'd rather have the new Kia diesel car - 92mpg on the extra urban cycle which is a stunning achievement. Take a passenger and it beats the "C5 on steroids". Having a wheel at each corner is jolly handy, it probably tows a small boat also.
I thought imperial gallons were bigger;I've got in my head that 1 imperial gallon = 0.8 US gallon.
My 1995 Citroen AX diesel does 70+mpg in normal use.
Probobly not as comfortable as the Kia but a fraction of the price.
Easy to work on too.