The autobahn is quite the experience, although the whole no speed limit is a bit misleading. There are sections of it that don't have a posted limit but that changes based on traffic flow, it's also only in more sparsely populated areas. When those no limit areas pop up though, be prepared, if you see a tiny dot in your rear view and are considering passing someone, there is a good chance you have about 7 seconds to do it before the tiny dot you saw is right behind you!