Not sure what all the heat is really all about here, but...

Two simple points for now.

It is NOT emphasized strongly enough - and the very title of this thread is fundamentally in error - that it is NOT Limewire or any other Gnutella Network client providing 'offensive' material.
Limewire is just one of many 'clients'.
The material is made available by individuals who happen to be using one tool/client or another. So, cease any specific references to Limewire or any other one client. Those who have posted with the conviction that there is some degree of responsibility due to any Gnutella Network client are only expressing their ignorance of the system and p2p networks in general.

And...

In the great majority of cases file recovery can be achieved very easily and at no cost...

Recuva - Undelete, Unerase, File Recovery - Home

Try it.
Be amazed... After so-called overwrites, defrags and 'cleanings' you will still be able to recover enormous amounts of data - either perfect clean files or partials that can be 'repaired' and certainly file names and locations.
Even the Piriform 'Secure Delete' function doesn't really wipe anything !!!