yes they are allowed on the highway. However these vehicles are more hype then anything. The actually don't get very amazing gas mileage when tested in the real world, check out road and track's stats. If i were you look at something like a yaris or nissan's compact that will have more storage space, will be faster, get similar gas mileage and will be better looking .
that's not true.
Smart cars are certified cars to be driven in the city and highway.
they also are safe cars, even tho they are small.
they are legal in all 50 states, and again, they are legal to be driven in the freeway.
=)
check with you local state rules for speed restrictions... I have seen them on the freeway in California and they are a european car with thir autobon and faster speedlimits .