The Atom CAN be street legal... but they are usually registered as kit, or recreational vehicles.
A customer of mine in California just got his roller, so sick. I'm helping him get the wiring for the engine, he is building a 300whp all motor 2.4l K engine.
Seems like a small price to pay to be able to destroy anything on the street and the track.
This is his...
I think this one without the engine is around $30,000... the track package with the supercharged 300hp setup is about $60k.