If you go for the girls Czech and Hungary are good places to go, if you want beaches stay away from Italy in August - too expensive and crowded! But if you want culture both Paris and Italy are great in August, because the cities are quiet since all locals are at the beach.
Great beaches with less crowds (but great surf): coast off Bordeaux in France with the biggest sand dune at Arcachone (or whatever the spelling is).
Being German I recommend Berlin and Cologne, and go and see some smaller towns in Germany off the really beaten track (avoid Heidelberg and Munich = tourist traps for Americans! Freiburg on the swiss border is as nice as Heidelberg, but not so crowded.)
If you stay a little longer: BUY A CAR! Lot easier to travel, and trains are really expensive
