A good way to keep a large percentage of spammers away is greylisting: http://en.wikipedia.org/wiki/Greylisting. Simple and clever, if you can take time to understand it, because it stops the spam before, instead of junking it after it was transmitted.
@Mary Yugo Your address is in the clear to anyone that receives vortex-l messages, I see it, but also many sites that mirror vortex-l messages see your address and put it on a web page. Usually the software managing a mailing list can do the hiding solving the problem once for all. But it is not the user fault: it is the spammer that is violating the law. Should we give away the freedom to use our real id, because of some criminal spammer? mic 2011/12/31 Mary Yugo <[email protected]>: > Geez, folks. If your email address is open to the world, as it is on this > email list, you will get tons of spam. You should never post your email > address on the internet except in the form: "maryyugo [at symbol] yahoo > [dot] com" so that a human has to interpret it. And it is best, for > purposes like this mailing list, to create a new email address which is only > for this purpose. It also cuts way down on clutter.

