If you think this is cool, check out Google's new Project Loon: Balloon-powered Internet access. Here is a quote taken from Google Blog
about their idea behind these balloons:
We believe that it might actually be possible to build a ring of balloons, flying around the globe on the stratospheric winds, that provides Internet access to the earth below. It’s very early days, but we’ve built a system that uses balloons, carried by the wind at altitudes twice as high as commercial planes, to beam Internet access to the ground at speeds similar to today’s 3G networks or faster. As a result, we hope balloons could become an option for connecting rural, remote, and underserved areas, and for helping with communications after natural disasters. The idea may sound a bit crazy—and that’s part of the reason we’re calling it Project Loon—but there’s solid science behind it.