Graduate students who are interested in large-scale networks should read this post by Tom Lento, who is a data scientist at Facebook (and a Cornell sociology grad), about Facebook’s new graduate fellowship program.
It’s pretty frustrating that, given the quasi-social science Facebook is doing, the listing does not explicitly mention social science disciplines, but I have gotten word that social scientists with appropriately strong computational skills (i.e. candidate should be a reasonably competent programmer) can be considered.
That said, it’s great that Facebook is willing to work with academics, especially graduate students, to do interesting things that might have some general scientific benefit (in addition to direct product benefit). This puts them in the category of Microsoft, IBM, HP, Google, Yahoo, and other such tech companies, who also fund sizable graduate student internship programs.
Facebook has a treasure trove of micro-level interaction data. If you want to work with that data, this might be the best way to do it.