Graphing Purchases on FredMiranda

Here’s an applet (based on TouchGraph) I put together for depicting relationships between buyers and sellers at an http://www.fredmiranda.com buying and selling forum for photography gear I frequent. Every node in the graph is a username and every edge corresponds to a transaction with the user connected to by the edge. I currently do not have a directed edge to show who bought or sold because that’s not necessarily easy to parse from the free text part of the post. I’d love some suggestions for improving this and maybe some cool applications for the data if it were in RDF. Here’s the long story. http://torrez.us/code/fredmiranda/demo/