DIY eMail Filtering
Mail Filtering - Introduction This site is mostly an excellent how-to & discussion on effective email server management & email protection.
Perhaps if the ISPs would wise up and start doing the same, BASIC stuff - end users wouldn't have such a friggin SPAM problem. Oh-the software & utilities used are all free & open source.
So why don't ISPs do this and save everyone from their SPAM nightmares and perhaps reduce costs...because they are clueless, clueless bastards.