Yup, the 'messages in the comments' aspect reminded me of the early days in mid to late 1990s.
I will get round to doing a mind map in this. A 'run time' steerable navigation mode would be great (I tend to do 'random walks' while teaching, and I use slide sorter view a lot during lessons).
Pt1: http://www.youtube.com/watch?v=AFA-rOls8YA Pt2: http://www.youtube.com/watch?v=CeLrlmV9A-s
(The rest of the series is quite fun as well -- and impressive for an indie outfit)