I've discovered that the BD-5J has been turned into a car about a 1000-times, by one engineer after another. But no automotive manufacturer has ever marketed it.

Specs:

Cabin Length 64 in.
Cabin Width 23.5 in.
Cabin Height 36 in.
Empty Weight 432 lbs.
Gross Weight 860 lbs.
Useful Load 428 lbs.
Fuel Capacity 36 U.S. Gallons
Engine Weight 84.88 lbs
Range 280 miles
Top Speed 320 mph.

Turn this into a street bike!!! Lop off the wings and the empennage. Put a 28 hp engine in, flex-fuelled, or maybe diesel or hybrid, mount some street tires, and all-weather heat/air conditioning, CD player, and some deployable hydraulic outrigger wheels so it won't fall over when it stops for a red light. Oh, and some external airbags with range-finders to detect impending collisions, or maybe a faux hoola-hoop to provide a physical trigger for the airbag system. Make it as safe as a mid-size sedan. If it's the same price or less, and gets 150 mpg fuel economy, I'd buy one. I don't need two seats.