Hit up Salzburg while in Austria, it turned out to be one of my favorite cities in my trek across Europe. Friendly people, awesome architecture, cheap beer and easy to get around. Rarely ever need a taxi to get around, feet and bikes are the best way. The Salzburg fortress is really interesting, Mozartís house and plenty of beer gardens right down town. Red Bullís hangar 7 is pretty cool at sunset (Red Bullís headquarters is in Salzburg). If you want to take a drive there are the gondola and hang gliding trips in the mountains, and a tour of the Eagles Nest.
We hit up Munich while in Germany. A must is the Hofbrauhaus, giant brewery/restaurant, can get a little rowdy but always a lot of fun. The residence is really interesting if youíre into history but it can get a little long. The castle tour is supposed be pretty good although we didnít have time for it. There are beer/brewery tours that are a lot of fun. You could always stop by the Nurburgring on your way and give that a drive!
I canít speak highly enough about Salzburg and Munich, probably because of how friendly the people were while we were there, some of the most fun we had was fumbling through a conversation with the locals in broken German/English over a lot of beer. Have fun.
You can't tell because it was taken with a crappy point and shoot camera but there was a wakeboat running around on that lake. We took this from a bar in Salzburg, I've already decided I'm retiring there