I'm not sure hardware currently supports this, but it would be really cool if there was a web browser GPS control, header - or something to that effect.  Basically the idea is to be able to perform a search through your web browser that uses your GPS location as one of the search parameters.  This would be incredibally useful for handheld internet devices.  My navi in my truck already does this when I need to find a gas station, bank, or restaurant nearby.  Handheld browsers should be able to do the same without the user needing to manually input a GPS coordinate.  Think realestate listings.  You're driving down a nice neighborhood and you want to search for all listed houses within 3 miles, with GPS coords this would be a snap.  What if you are standing inside a store?  You could go directly to the store's web site just because you are physically standing inside it.  I think people would really dig this - I know I would.  What about location aware internet advertising?  This is just the tip of the iceberg, especially once everyone has a phone that also acts as an internet connectivity device.