How to deal with professional bashers/spammersWhile nothing is entirely effective, at least two strategies help hurt them and diminish their effectiveness.
1. Don't respond;
2. If you must, do not hit the reply button.
Such people get paid by the number of responses they provoke. If you don't reply, they don't get paid. If you feel that you must reply - and there is hardly ever a solid reason to do so - create a new posting AND MODIFY THE SUBJECT LINE. Then, do not address their alias. In this way, they can not so easily prove their effectiveness in eliciting the responses they seek. The more of these, the more they are paid.
My recommendation? Be smart; use the ignore feature.