social network site x graph-based interface x time

To literally see how the webs of relationships between people change. Take a graph-based interface of a social network, like Facebook's 'friend wheel' or TouchGraph's Facebook browser. Add the dimension of time in a way similar to this. And you get a graph-based visualization of how social networks change through time. Plus, if you moved from a binary to a spectral or typological understanding of connections between 'friends' (elaborated here), you'd likely discover some patterns.