Three wheels are fun. The Morgan 3 wheel from the 1930s was both fun and fast—especially the super sport. I would like to see a return to these small fast fun cars—mileage was great. It used a two cylinder motorcycle engine.
Morgan is still in business and makes both three and four-wheel cars.
They still make them:
http://www.morgan3wheeler.co.uk/home.html
A review:
http://www.motortrend.com/roadtests/convertibles/1208_2013_morgan_3_wheeler_first_drive/
According to the Wikipedia page, they have a US spec model, too.