Fixmystreet is a neat little project out of the UK, made to:

help people report, view, or discuss local problems they’ve found to their local council by simply locating them on a map. It launched in beta early February 2007.

You enter a postal code, are shown a map, click on the map, and add your comments about problems (graffiti, overflowing drains, broken lights, etc). An email is then sent to the local municipal council. As of today, 171 reports have been made in the past week, 381 problems have been fixed in the past month, and 2462 reports have been updated.

The project comes to you from MySociety, which:

builds websites which give people simple, tangible benefits in the civic and community aspects of their lives. For more info on our aims, click here.