Greg Gershman has built a cool application of Google Earth. You can jump from Blogdigger Local search results to Google Earth and see markers for all of the blogs in your geo neighborhood. The result looks something like this:
(That’s Greg’s image. Don’t have Google Earth running here, waiting for the OS X version. Impatiently.) Blogdigger seems to have found its niche with Blogdigger Local, and it’s a good one.