Imagine an open source location-aware browser extension for Firefox from Mozilla and Skyhook Wireless... it upgrades the entire web to understand location, enabling enriched, personalized, and localized content. Geode is based upon the draft W3C Geolocation API specification and is being released as Open Source software under the MPL, GPL and LGPL tri-license. From the Geode project... "Geode provides an early implementation of the W3C Geolocation specification so that developers can begin experimenting with enabling location-aware experiences using Firefox 3 today, and users can tell us what they think of the experience it provides. It includes a single experimental geolocation service provider so that any computer with WiFi can get accurate positioning data.
With Geode when a web site requests your location a notification bar will ask how much information you want to give that site: your exact location, your neighborhood, your city, or nothing at all. See http://labs.mozilla.com/2008/10/introducing-geode/