The New York City Blogger Map, http://www.nycbloggers.com/:
A map of the city that shows where the bloggers are, organized by subway stop. Find out who’s blogging in your neighborhood!
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You can click on the map to start exploring. The overview map will show you how many blogs are in each borough, and the borough maps will show you how many blogs are at each station. Click on the station to get the list of blogs. You can also browse by subway line, using the buttons on the right. And you can search for a specific blog by name using the search feature.