As everybody knows, social networks are all the rage these days.  What makes a network valuable is not just how many people are in it, but how many ways those people are connected.  So, if you own a social network, you need to not just work on adding people, but also on getting those people to create interconnections between themselves.

 One of the more interesting social networks out there is LinkedIn.  The graph maintained by LinkedIn is all about people's employment.  Naturally, it's inhabited by recruiters who pay money for the right to search LinkedIn's massive collection ...