The nicest are the pre-studied jokes:
"Those Germans surely aren't 3 times smarter than we are!"
"Want die Duitsers zijn heus niet 3x slimmer dan wij!"
Wouter Bos -- on the much better crime solving rate by the German police.
"Mr. Zalm, you said Wouter Bos doesn't know how do to his maths. But he was working for you when you were Minister of Finance, right?"
"Yes but... he was doing taxes there wasn't he?!"
"Maar ja, daar deed hij ook belastingen!"