On: Visualizing Networks with Hive Plots

[oscilloscope]

d3.js is ideal for custom visualizations like Martin Krzywinski's. Another neat one is the chord diagram, based on Circos.

http://mbostock.github.com/d3/ex/chord.html

http://circos.ca/

It's also straightforward to transition between datasets and layouts:

http://exposedata.com/tutorial/chord/latest.html