Security guru Bruce Schneier says library wifi makes the world a better place in his interesting piece about leaving wifi networks open:
And I appreciate everyone else who keeps an open wireless network, including all the coffee shops, bars and libraries I have visited in the past, the Dayton International Airport where I started writing this and the Four Points Sheraton where I finished. You all make the world a better place.
I agree. Finding free wifi in an airport is a real treat.