I'm very much into the same thing and yes you *can* get in trouble if your caught. Parks are always good as well as hiking trails. A friend of mine did it at a theme park earlier this year and said it was great (a project of mine for next...). I try to stay away from the car thing, its hardly comfortable and overdone IMO. The best way to not get caught is when you find a spot just be aware of your environment. Remember most government and federal buildings have external cameras and now quite a few major intersections do as well. Best of luck
If you find somewhere good please let me know!