> It isn't clear if you are looking to provide your user with some
> voluntary self-filtering or if your user wants to impose filtering on
> others.

Ah, apologies to everyone!  (I was curious about the "political" statement).  It is indeed *self* inflicted.  The user is having trouble getting his work done and finds his own behaviour online detrimental to his work process.

> People gave you ideas about the latter.  For the former there
> are various browser plugins that your user can install to self-manage
> their own filtering.  For example Chrome's "Personal Blocklist"
> extension.  Although the emphasis there looks to be default-allow rather
> than default-deny.

I figured if the user has issues to the point of requesting that I whitelist websites he may not find a plugin for browsers useful (i.e. easy to circumvent), however, I did encounter these options as well in my google searches so I will suggest this as an option.

Thanks everyone!
-Chris