"While Mapquest and its ilk are incredibly useful when planning a road trip, when it comes to navigating a city like New York these sites don’t necessarily help you plot your next jaunt from the West Village to Yankee Stadium. Which is where HopStop comes in. HopStop allows you to map your trip using the subway, crosstown buses and your own two feet. With cool features that allow you to choose a route with more walking and fewer transfers (and vice versa), a time estimate that takes into account your time of departure, and a fast, clean interface, we’re already hooked."
http://www.hopstop.com