All the water and air on earth gathered into spheres and compared to the Earth - Boing Boing

"Left: All the water in the world (1.4087 billion cubic kilometres of it) including sea water, ice, lakes, rivers, ground water, clouds, etc.

Right: All the air in the atmosphere (5140 trillion tonnes of it) gathered into a ball at sea-level density. Shown on the same scale as the Earth."

http://www.boingboing.net/2008/03/11/all-the-water-and-ai.html