Sleeping in your car... in most places, it shouldn't be dangerous but that all depends on where you stay. And you should check local laws first, in many states, it is illegal to sleep in your car outside of designated rest stops. You can get pretty cheap hotels outside of the really popular areas during peak season. Or there's always hostels. And like Mythos says, it's a pretty darn big place. I personally think the northeast (Massachusetts, Maine, Vermont) and the northwest (Oregon, Washington) are beautiful - especially in the Fall. Some popular locations... Washington D.C., Times Square in New York, Las Vegas, New Orleans (or what's left of it?), Florida Keys, the Alamo, San Francisco/California, Mount Rushmore. Obviously you can't expect to see a whole lot of the country in two weeks.