One of the reasons I love NY is the spirit of community that is prevalent in the city. If you've never been to NYC put it on the list of things to do before you die.
The Alliance for Downtown New York has been working to enhance the quality of life in Lower Manhattan since 1995. They have an exceptional website put together by people who are genuinely passionate about their community and NYC.
One of my favourite projects they're working on is "The Doors of Lower Manhattan Challenge". Identify the doors of Lower Manhattan correctly and win!
Next time I go to New York I'm renting a bike for free!