Are you looking for a directory of wi-fi nodes in your city? You can find a list of nodes for almost anywhere in the world if you search The Wireless Node Database Project website.
The projects lists, catalogs and presents a searchable database of wi-fi nodes, including maps. Users can add comments about the nodes (like a wiki), find out about free and commercial nodes, and lots more.
One great feature is a search for nodes in a 10kms area around you.