The Democracy Collaborative at the University of Maryland has a wonderful set of resources at http://www.community- wealth.org/strategies/index.html.
Here are a few ideas and models for Community Building and Co-op Projects:
* Vertigo and the Intentional Inhabitant: Leadership in a Connected World, the story of Lawrenceville Community Works
* Energy and the Environment
Home energy audits and home fix-up
Encourage neighbors to recycle. Here's a fabulous story and video about what's being done in a New York housing complex.
Sharing lawnmowers, tools, etc.
Neighborhood and alley clean-ups
* Start or work on a community garden
* Although the social media -- Web 2.0, Twitter, Facebook, etc. -- are nice, there's plenty of evidence that face-to-face interaction remains the best way to connect with people. As John Gardner put it, "[W]e want to take each other's measure face-to-face. We're more primitive than we think…We want to hear the tone of voice and see the body language."
Town Halls by Invitation by James Fishkin (New York Times)
* BetterTogether's "150 things you can do to build social capital"
* Neighbor Circles, a concept developed by Lawrence Community Works, is thoroughly explained at http://www.typp.org/media/docs/0155_NeighborCircles.pdf .