It is a tough situation. I _voluntarily_ set my MS Outlook filters to trash all incoming messages based on their content, such as ads offering V.i.a.g.r.a, p.e.n.i.s. e.n.l.a.r.g.e.m.e.n.t and similar services (the above spelling will most likely fool content based filters) as well as offers from N.i.g.e.r.i.a.n. banks. It works most of the time (unless spammers come up with some creative spelling) but it also filters out some lbo-talk messages, especially those with body parts references.
I think that is the price we pay for spam.
Wojtek