Hiawatha gets the point for a complete answer.
Proximacentauri (real identity not known) is a Flickr user who posted photos of the building process of this homemade racer. According to Wired, "Proximacentauri says his Ariel Atom clone, which he calls Z59, cranks out about 160 horsepower and does 0 to 60 in 4.5 seconds - just under a second behind the real Atom. The car's street-legal and registered, and Proxicentauri claims it gets 35 mpg."