I've been building a social network application at the core of my dissertation. While I've had a (semi)stable version of a complete package up for a while--one that reads messages into a database and shows views of the output, it's hard to get that one going.
It takes somethng like half an hour to scrape all the headers into the database. I'm working on improving that code, but I don't expect it to get much better.
So as a preview of how things look, I've put up an application pointing to my own data. I've loosely anonymized all the names--so you can just make up the stories around them, if you like.
Check it out:
DEMO of Soylent
(Warning: 1 MB jar download, followed by a few megabytes of SQL query, followed by more information when you click on a name. Fast, it isn't.)
Let's take a moment to figure out how this image works. Remember that all this is pretty new; the interface changes frequently.

This display is a view of my email interactions with one other person. I am said to be "interacting" when I send them a message; I also think about connections, which are the people to whom I have carbon-copied a mesage.
When the UI is up, you'll see something like this four-panel view. The left side has a list of people (names encrypted); in this case, I've chosen the fifth down (Hnrvng VKXW). The top panel is scrollable, and tells me that I've exchanged 522 messages with Hnrnvng.
The second panel shows the frequency of, in order:
In the bottom panel, you can see (and click, a little bit) the three people with whom I collaborated most with Hnrvng: "Qqoxwujs", "Ncuo", and "Qcxp". The color of the tie gives a rough idea of its age: yellow is recent, red is old. That is, it's been quite a while since I connected Ncuo to Hnrvng (I co-TA'd with Ncuo when I first arrived at UCI); some time later, I worked with Qqoxwujs and Hrnvng more recently (when we collaborated on a paper with the three of us as co-authors); most recently, Qcxp was involved in some of my bureaucratic hurdles. (You'll note that Qcxp has a prominent spot at the top of the display; he has been a major figure in my work life.)
Got it? Great. Here's a screen shot of a more complex image, with a person who has been involved in several different social contexts...
View image