Visualization of graph data is incredibly challenging, particularly when it comes to extremely large, scale-free graphs and social networks. A few simple searches on the Web and you will find some mesmerizing and very cool images. Perhaps the most cited...
B. Pereira Nunes, R. Kawase, S. Dietze, D. Taibi, M. Casanova, und W. Nejdl. Proceedings of the Web of Linked Entities Workshop in conjuction with the 11th International Semantic Web Conference, Volume 906 von CEUR-WS.org, Seite 45--57. (November 2012)