http://www.go2itnetwork.com/making-four/

Is it possible to make a four wheeler legal to drive on the streets like a motor cycle or a car?
And if it is possible what are the requirements of making it legal to drive on the road. For instance, one of my friends said it’s legal to drive a four wheeler on the street as long as you have a driver’s license, insurance, a registered license plate, rear view mirrors, front and tail lights, and then you’re good to go. Is this accurate? Does it vary from state to state?
It is legal in some states, but the ATVs and drivers must be licensed and insured just like a car. In Idaho, they can only run on streets where the speed limit is below 45 MPH.
DigitalPh33r’s Guide to Making Halo 3 Machinima: Part Four