I and my partners run an email hosting company called geekmail.cc. We're presently testing a feature called greylisting which seems to be effective against approximately 90% of spam overall.
The great thing about greylisting is that spam never makes it to the user's folder, there is no possibility of false positives, and it's impossible for spammers to detect that we're using the feature.
This takes a lot of the workload away from SpamAssassin (which we consider to be a rather blunt weapon that generates a lot of false positives) and doesn't upset the users.
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The great thing about greylisting is that spam never makes it to the user's folder, there is no possibility of false positives, and it's impossible for spammers to detect that we're using the feature.
This takes a lot of the workload away from SpamAssassin (which we consider to be a rather blunt weapon that generates a lot of false positives) and doesn't upset the users.
-BvB