This dataset was created by an intern at Facebook who plotted 10 million pairs of friends on Facebook. The result is a stunning map that shows the connections between people and highlights the regions with readily available access to the internet. Africa, with limited internet access is rather dim, while China, with many internet users is dim due to the use of a popular Chinese social networking site and government restrictions.
From the creator upon refining the visualization - "After a few minutes of rendering, the new plot appeared, and I was a bit taken aback by what I saw. The blob had turned into a surprisingly detailed map of the world. Not only were continents visible, certain international borders were apparent as well. What really struck me, though, was knowing that the lines didn't represent coasts or rivers or political borders, but real human relationships. Each line might represent a friendship made while traveling, a family member abroad, or an old college friend pulled away by the various forces of life."
For more information on the creation of this dataset, visit here