Where can I find out about how to integrate SpamAssassin with (some mail system)?

There's a whole load of integration glue out there, integrating SpamAssassin with virtually every mail system. To keep track of them, there's two places:

http://news.spamassassin.zawodny.com – the SpamAssassin news site; this is the most up-to-date.

http://spamassassin.org/where.html – the "Where SpamAssassin is Used" page on the main website. This is now mostly superceded.

If you've come up with a new tool which supports SA, please post a submission to the news site using the "Submit News" link.