First, I parsed out an email folder to create a hashmap with sender recipient pairs. Afterwards, I iterated over the map to create another map of name, Node pairs. A Node contained a hashmap of name, edge pairs. An edge contained a weight and a pointer to another node. I drew the verticies recursively from a starting node to two levels out.
Check out these screenshots:
More levels:
More stuff:
Printing out the names shows interesting relationships between the nodes. Here we see mass communications occurring between Enron CEO Keny Lay, his secretary, and Enron's Head of PR:
Assigning the links different z-values let's us peel the links out like an onion and see only the high density links:
The Enron public data set is available at here.