[toaster] Spam Service / Solution (slightly off topic)

[Maxwell]

Hi, I thought I'd query the list about anti-spam services.  Does anybody
have any recommendations?  The spam assassin, rules du jour, etc just isn't
cutting it.  I've seen services like ems.netriplex.com , mxlogic.com ,
appriver , but have always had mixed results.  Does anyone have any good
advice for a solid anti spam service especially that can be configured for
many domains with many users?