I was part of the Oxygen Fueled Car crew, a 1989 Honda Civic turned into a tandem bicycle for Savannah, GA's 2005 International Car-Free Day. We did some research before building to avoid being pulled over, and rode all around town without any tickets at all (except for a nasty note from a bed and breakfast).

A car without a motor but with pedals is not a car anymore, just a big bike. It doesn't need a licence plate, insurance, a title, inspections, etc. It does need to meet the requirements of a bicycle, though: in most places this means stopping in a certain distance, lights for nighttime use, and obeying traffic rules. Our 'car' stopped fast with its original back brakes, steered tigher than it did when it was whole, and moved about as fast or faster than Savannah city traffic.

In practice, we found the least conflict in being a bike sometimes, a 'car' sometimes. We would ride in bike lanes and on sidewalks only where bikes were allowed (a civic will fit about anywhere if you're daring) and would take the lane (as the law allows) when it was in our best interest and safe.

We also didn't have a horn, but did have two bike bells.

www.o2fc.com