Keith Hampton at MIT is making publicly available his I-Neighbors service. It lets you find, or create, an online presence for your block or neighborhood. Unlike previous incarnations in the commercial realm, which were hot a few years back, this one seems to focus on person to person connections at a much finer granularity.
Many of the features will look familiar to people who have set up YahooGroups before, but there are a number of features that take advantage of geograhpic proximity information. Definitely worth a look if you’d like to create more social connections *or* more political activity in your neighborhood. Even has a carpool finding feature, though it doesn’t try to real-time matching.
Keith developed this software for use in field studies of four Boston neighborhoods. He hasn’t written up the results yet, at least not for public consumption, but he describes some of the results in an interview. Sounds pretty amazing!