One of my favorite applications on the web is a free Java application called TouchGraph Google Browser. I use it to help in everything from finding inbound link opportunities to planning a linkwheel strategy and even helps with reputation management projects.
There are a couple tools available on the TouchGraph site, but the one I use is the free TouchGraph Google Browser tool and you can find it here: http://www.touchgraph.com/TGGoogleBrowser.html
