visone - analysis and visualization of social networks Great tool, but be sure to backup your work before analyzing the input.
See this example between 136 nodes with 424 links:
7 nodes have a connection probability of 0%, (outer nodes)
6 nodes = 0.59% conn. prob., (nodes on blue dotted circle)
1 node = 0.60% conn. prob.,
34 nodes = 0.68% conn. prob. (outer circle)
66 nodes = 0.79% conn. prob. (middle circle)
1 node = 0.80% conn. prob.
21 nodes = 0.95% conn. prob. (inner circle)
Also very good for analyzing webs of lies.