It's been a very long time since I ran a mail server, but for a decade or more I pumped all our outgoing mail through Hashcash because it gave a good boost to the Spam Assassin score. We'd crank it through the largest one, and it would add ~60sec to the mail delivery, unless we had a bunch of outgoing mail, but it was worth it I felt.
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It's been a very long time since I ran a mail server, but for a decade or more I pumped all our outgoing mail through Hashcash because it gave a good boost to the Spam Assassin score. We'd crank it through the largest one, and it would add ~60sec to the mail delivery, unless we had a bunch of outgoing mail, but it was worth it I felt.