Quote:
Zürich said:
Avoid Belgium, too much trafic.
Too much damn traffic everywhere these days!

You just have to avoid Brussels around rush-hour time, and you could get lucky.
Try: Calais - Ostende - Brussels - Liege/Luik/Lüttich (Same place, different names!

) - Aachen - A4 towards Köln, but leave it to head south on A61 past Bonn, Koblenz, eventally Hockenheim

, joining A5 towards Karlsruhe, follow signs to Basel and , if you're lucky you cross the German/Swiss border after 8 hours driving time at speeds which won't get you into too much trouble.
It may not look like the most direct route on the map, but it is one of the fastest because there are fewer gaps in the Autoroute / Autobahn links.