highlighting "weird" characters...

Hi all,

I use VIM - Vi IMproved 7.0 (2006 May 7, compiled Feb 23 2007 22:17:23)
to write mainly XHTML/PHP and I sometimes have to get content from word
processed documents and paste it into Vim for HTML markup.  This usually
results in having non-visually detectable characters (which I assume are
high ASCII) which display strangely on the Web.

Is there a way I can have my Vim highlight these characters so I can see
them and replace them with their HTML counterparts?

I've searched Google, the Vim e-mail archive, and I've helped Ugandan
children :),  but I'm no closer to the answer.

Any hints?

Thanks,
Mitch
Freeville, NY