I don't know of any pre-packaged solution, but I imagine that whipping up Graph objects from a crawler output wouldn't be too hard.

Then you can use Graph::ReadWrite (specifically, the Graph::Writer::Dot module) to dump them to a .dot file (for use with http://www.graphviz.org's dot tool). This gives pretty graphical output, though sometimes big.

It never ceases to amaze me how much more impressed the pointy-heads are when you have pretty pictures.