We rented a car and drove from Munich to Castle Neuschwanstein (around 50 miles IIRC.) I wasn’t driving, but I don’t remember much difficulty.
[QUOTE=Nava]
The “keep to the right” rule has a caveat in busy, multi-lane traffic on areas with lots of exits. Since the right lane is the one most commonly used to join and exit the highway, people who aren’t doing either will often stay in the second-from-right in moderate traffic, rather than weave constantly.
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Good point. Once you get into large cities with multiple lanes the driving is pretty much exactly like the States, with some exits on the right, some on the left, and everything slows down to familiar speeds & lane changing.
I lived in Germany for over two years. I never found Autobahn driving stressful. Everyone knew the rules and as long as you followed them there was no problem. They know how to drive at high speeds so I felt safer on the Autobahn than on many busy American highways. No one is weaving in and out of the lanes. Stay right. Pass left. Get out of the way when they are flashing their lights.
Warning: they drive like idiots in the city. Throw out all thoughts of “everyone follows the rules”.
[QUOTE=levdrakon]
Another corollary is not to assume your rent-a-car can keep up. An American can quickly adjust to German driving, but just because you’re driving a German car on a German road doesn’t mean your car can actually handle some of those high speeds safely. The people passing you at 110MPH are driving cares designed for it. Your rental probably isn’t, unless you’ve specifically requested a high-performance car. Basically, just because there’s no speed limit, doesn’t mean your car doesn’t have a speed limit.
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To be fair, 110 MPH is about 180 KPH. That’s quick for sure, but nowhere near dangerous for most modern cars. Your average Golf rental car will do that speed very safely and securely, with ample braking power.
Personally, when driving in Germany, I find myself cruising between 160 and 180 KPH. It’s not a whole lot faster than most of the traffic, and it means you’re not going too much slower than the 911 Turbo coming up on you, giving you some more time to get out of the way.
Then again, what with speed limits and consequent cameras being so predominant in Holland, I can’t help myself to go for top speed whenever I’m in Germany and the situation warrants it. Last time was a trip to Cologne, on which I was able to max my Alfa Romeo GT at 217 km/h on the clock. Not too impressive by Autobahn standards, but nice to be able to do it without risking losing my license (which is a very real chance in Holland at that speed). 
If you’re on the autobahn and you see someone coming up behind you with their left turn signal on, get over…NOW. They are usually hauling ass and will be on top of you before you know it. The left turn signal indicates their intent to run you off the road if you don’t yield. OK not really but that left turn signal is a polite way of saying EXCUSE ME COMING THROUGH!
Also, many non-highway signs have two speeds posted on them. They’ll have a picture of two cars next to each other and have numbers that look something like this: 50|100
This means that when no one else is coming, you may go 100 kph. However, if someone is approaching you from the opposite direction, you must slow to 50 kph.