Touchgraph is a pretty cool visualisation tool. And even though the free Google Touchgraph is just a demo with very limited functionality I often use it to check how deep a campaign or a brand is linked.
Thanks to Alina I just realized that they also have a facebook demo which displays as many of your contacts as you like. It's looks like my facebook Universe with me in the center of course and everybody of my facebook contacts rotating around me :)
As you can see it clusters people from the same region as well as friends who are connected to each other.
This is just a screenshot but you can click around and see who your friends are connected to as well. Go play around.