Thank you for the additional comments! I'll grap a map and then I'll get a better clue about what you all are talking about. But anyway, they are really appreciated.

I was looking at the Munich Airport website and found out that they had (free, I presume, as nothing about fees are mentioned) wireless internet access in quite a lot of places. This is really great! No need to find a phone...

The other day I went to Schiphol and their wireless lan for a flat 10 euro per day worked great. Narita has one as well but the providers which can access the wireless lan network are rather limited. I hope more and more airports will setup their wireless internet connection... hopefully for free or for a small fee!