I like mindmaps, I make a new one for each class I teach or for an article or book that I want to analyze. I used CMAPTools for a while but now I like MindMeister.
Invited guests can collaboratively edit the map in real time. I often do so in conjunction with a Skype conference conversation.
Click and drag the map around, click the + signs to open the nodes. Click the arrow icons on the nodes to go to a web page. Click on the full screen button to get the full effect. Just get in there and click!!