A Journey to a Thousand Maps Begins With an Open Code - New York Times

A Journey to a Thousand Maps Begins With an Open Code - New York Times: "An army of programmers, most of them doing it just for fun, has grabbed the software code that generates the distinctive maps with their drop-shadowed virtual pushpins, and combined it with other data like the locations of potholes, taco trucks and U.F.O. sightings, and even the sites of murders and muggings.
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Google's openness to the use of its maps does have limits, though. Once a mash-up turns into a large-scale commercial enterprise, Google looks to share in the revenue. That is happening at Trulia; Google lawyers are trying to negotiate a royalty agreement. "At the moment it is free," Mr. Flint said, "and we are taking advantage of it.""