Demonstrates how to dynamically add and remove nodes to a force diagram. This was functionality that should seemingly be easy, but was surprisingly hard. Many people were asking how to do this in forums, and this final product is the amalgamation of several commenters half baked (but not really functioning) solutions.
This one demonstrates changes in a social network diagram as relationships are added, removed, and updated. Add nodes by name, add links complete with custom lengths.
Also shows how to add labels to a force diagram.