From the July 2006 issue of Entrepreneur

Go to Google Maps and type in "Chicago airport." Click the "Satellite" button to view the satellite imagery. Zoom in two or three clicks until O'Hare International begins to take shape, then travel north a few clicks-bull's-eye! There's the Target store.

Like Target, businesses around airports have been advertising on their rooftops for years, knowing that overhead traffic brings an audience. With the explosion of satellite imagery on the internet, every rooftop in the country is now a trafficked fly zone. So should entrepreneurs paint their roofs?

Before you grab your paint bucket, consider the fact that the satellite images used by Google and others are not live shots-many are years old. So if you paint your rooftop, don't expect immediate results.

"If you're going to paint your building, you probably should be in a fast-growth area," says Perry Marshall, founder of Perry S. Marshall & Associates, an Oak Park, Illinois-based internet marketing and consulting firm. Marshall explains that search companies are more likely to update these areas to keep their information accurate: "This stuff costs money, and they're only going to update where they need to."

While painting your rooftop may be a good long-term strategy, you can get immediate results by creating a map mash-up. Map mash-ups combine maps with related information-anything ranging from census data to information on American Idol contestants. For its final season, The Sopranos' website partnered with Google Maps to highlight the locations of the show's fictional characters-even linking to video clips.

A map mash-up could be a great marketing tool for a business with multiple locations. Whether you use your rooftop as a billboard or use the power and creativity of mash-ups, one thing is certain: Cartography hasn't been this hot since the Age of Exploration.