GeoURL is another snazzy way to create a linkage between Internet and physical geography. It helps you create a couple meta tags expressing your meatspace coordinates, which you stick in the header of your blog. You then ping it, and it adds you to its list. This could help make some interesting things possible, apart from just figuring out who your real-world neighbors are in the blogosphere.
This also led me to the ACME mapper, which showed me a 1 meter-per-pixel image of my street, shown here.