This is an animation made by Stamen for Trulia showing related searches... the caption shows the current city, lines show where people searched for after the current city.

This is an animation generated by a realtime interactive application that allows you to fly from place to place along the search connections.

It's kind of an Amazon Recommends ("people who searched here also searched there") for real-estate.

It's interesting to see the difference between cities where people subsequently refine their search down to a neighborhood, compared to cities where people subsequently search for another city nearby, or into another state entirely. Could these connections lead to a community definition of 'peer cities'?

Stamen had the pleasure of working with Ryan Alexander (onecm.com) on this visualization.