VisualComplexity.com has a nice assortment of visualization of complex networks, including social networks. Visualization of social networks is an important endevour in summarization of data about social networks. Here is an excerpt from the website which describes the site.
VisualComplexity.com intends to be a unified resource space for anyone interested in the visualization of complex networks. The project's main goal is to leverage a critical understanding of different visualization methods, across a series of disciplines, as diverse as Biology, Social Networks or the World Wide Web. I truly hope this space can inspire, motivate and enlighten any person doing research on this field.
The URL is as follows: http://www.visualcomplexity.com/