There's always this list, linked from the bawug website (http://www.bawug.org/projects/):
http://www.toaster.net/wireless/aplist.php It's supposed to cover the bay, but it's jam packed with SF AP's. tack -- general wireless list, a bawug thing <http://www.bawug.org/> [un]subscribe: http://lists.bawug.org/mailman/listinfo/wireless
