I started coding this idea a while back, but had to abandon it for lack of time: A site for civic associations that allows them to post announcements, coordinate events, and collect dues via a credit card.

Because civic associations in my area are voluntary but handle essential services such as snow plowing, I came up with a novel way to guilt residents into paying their dues: A Google Map showing which households were up to date on their dues -- a way to subtly pressure neighbors to pay their fair share.

Site could also include a neighborhood marketplace -- sort of a hyper-local version of Craigslist -- and other tools useful to civic associations.