Of all things, I forgot to mention the most ubiquitous drinking we participated in while in Europe: Mineral Water
Don't touch the stuff!
Get drunk off wine & beer all day if you have to, but stay away from the mineral water.
I expected this problem with mineral water (eg, Evian) since I had the same problem the last time I visited Europe. At first, it's not so bad especially if it's ice cold, but after a a couple of days, mineral water just leaves a wierd taste in your mouth. After a week you just gulp the stuff so as not to taste it. After two weeks you just go thirsty. The one thing I wanted to do when returning to the states didn't involve a shower or a bed, it involved a bottle of Aquafina. Nuff said.