I've come across quite a few free WiFi networks, but I've invariably had difficulty actually connecting to anything I want to use - be it Met sources or non-aviation stuff like Skype.
I did manage to connect at a Spanish airfield, but half way through reading the TAF it asked for my credit card number...
They've just put free WiFi in the Norfolk village, as an experiment for one year. I'll give that a whirl next time I'm up there, to see if I can do any of those things.