There's a really nice little iOS app (currently iPhone only) called Vizz that visualises your LinkedIn network.

You can see what industries your connections are in, where they're located, what companies they work for and who's changed roles recently.

Quite a useful little app, all for the princely sum of £0.69 (69p).

Admittedly I do know the author @hakimmobile, but that doesn't change the usefulness of the app.