Finally tiring of all the garbage, I found this open source package and recognized it as the
best of breed, smiling at the fact that the US spends billions on
spam blocking but this package which works excellently is free.
One thing you should know is that the task of recognition and seperation of spam from ham is quite complex and never ending. Since the spammers are constantly at work, so must the spam blockers be. This leads to a major concern you should be aware of: quite rightly Spamassassin concentrates only on the task of spam recognition. This means that integration with your email package requires another package and this can be a significant task in it's own right.
Like most Unix users, I use Sendmail as the MTA and it is notoriously complex and difficult to administer. In my first try at the integration I discovered what would be ultimately the package of choice for the Spamassassin-Sendmail integration, "milter-spamc" ( snert.org ). Unfortuately, in the first attempt I stabbed myself in the foot and crashed my glibc 2.2 based system by trying to force a series of rpm upgrades required for the ensemble of packages (milter-spamc requires the latest Sendmail). To make a long story short, the solution was to abandon the use of RPM and rebuild the current sendmail from the distributed tarball, though some rpms were used in ancillary packages.
milter-spamc provides a fine level of control on the dispositon of junk mail. In practice, as it turns out, Spamassassin generally gives ham a score near 0, though some special kinds of messages give scores as high as upper 2.n (for example I have a convention of using bodyless emails as instant messages). I've found setting the spamassassin level to 2 then setting milter-spamc reject-excess to 1 and discard excess to 3 works best. With these settings, anything between 3 and 5 is rejected by Sendmail (SMTP 550), anything over 5 hits the bit bucket and anything between 2 and 3 shows up in your mailer with the subject prefixed with "[SPAM]".
Update:
After almost 2 months of use and monitoring operation, I've found this setup eliminates most Spam, on some days 100% percent. Had to backup to set reject-excess to 4 and drop-excess to 7 though since some of my own mails were being rejected (mostly from using a sticky IP) like the E user id mails. Should also note that will probably put on new web head I'm building with the settings above since 1) it has a fully static IP and can tolerate the tighter setting and 2) I've realized that this setup prevents mail relaying exploits as well as skank shit showing up in ones inbox.