Google Earth is probably the most appreciated Google software and it's based on Keyhole, a commercial software that's now free. When it was acquired, Google said "with Keyhole, you can fly like a superhero from your computer at home to a street corner somewhere else in the world" and that's true. Google Earth allows you to view the world from your armchair, to discover secret corners and to explore dangerous places. It's like being Phileas Fogg from the famous book by Jules Verne, Around the World in 80 Days. But Google Earth is also valuable from a scientific perspective, as it creates a 3D interface for geographic information. Spiegel explains how Google Earth is changing the science and our life as well:"Google Earth wasn't really intended for scientists. The Google search engine's extraordinary globe, which is made up of hundreds of thousands of satellite photos and aerial images, was initially meant as a game for virtual hobby pilots. Users discovered that it was fun to fly over their own homes, swing up into space and, within seconds, swoop back down into the depths of the Grand Canyon. But now the scientific community is discovering how useful the software is for their own work.
With a single keystroke, biologist Born superimposes colored maps over the Arctic. The maps show him where the ice sheet is getting thinner and the direction in which the pieces of floating ice on which walruses like to catch a ride are drifting. All of the ice data, which comes from satellites and measuring buoys, is available on the Internet. [...]
Google Earth played an unexpectedly useful role in the wake of last summer's disastrous flooding in New Orleans following Hurricane Katrina. Within just a short time after the hurricane struck, Google Earth had already added 8,000 post-disaster aerial photographs of flooded areas taken by the US National Oceanic and Atmospheric Agency (NOAA). The images allowed disaster relief workers to scan areas on the computer and search, for example, for passable roads."
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