Attempting to conquer the same social/hyperlocal space as Patch and more niche apps like Yardsale, Nextdoor, which launched to the public last October, lets people create Facebook group-like communities for their neighborhoods, free of charge.
From the Village Voice to Foursquare to Everyblock, everyone has tried, but the problem of how to effectively create location-based social networking is a conundrum for many reasons. In order to mitigate the largest barrier to entry, trust, Nextdoor has you verify your neighborhood address either via snail mail or via credit card - purposefully introducing friction.