Try this web site for "10 Great European Drives":
http://msnbc.msn.com/id/6895250/
I've been over 3 times. I recommend anything in Austria, Switzerland, Northern Italy, and the Black Forest area of Germany. Incedible roads and scenery. Summer isn't the best time to drive these roads. All of Europe is on vacation and the many tour buses hold up traffiic. While in Florence, I was told that in the summer, 2,000 buses A DAY come thru the city....