SpamAssassin Benchmarks - Fighting Spam Faster

I've been working to combat the recent wave of spam we've all been experiencing - waves upon waves of St0ck Reports, and Vlnnagra and Home M0ortgage Appr0vals. In doing so, I've done some benchmarks on SpamAssassin with its various options that some Google searchers might find ineresting:

The following numbers were produced on a test server of mine - a Gateway E-9315R server, 3.0Ghz Xeon, 512MB RAM, 80GB SATA, Fedora Core 3, running Postfix 2, MailScanner, and SpamAssassin.

• All features turned on: 4.8 messages/min
• Bayes filtering disabled: 19.1 messages/min
• SpamAssassin disabled, but RBL still turned on: 74 messages/min
• RBL+XBL, Pyzor, Razor and DCC disabled in spam.assassin.prefs: 76 messages/min
• RBL+XBL disabled in MailScanner.conf (line commented out: Spam List = ORDB-RBL SBL+XBL): 320 messages/min
• RBL+XBL disabled, but SpamAssassin turned back on: 64 messages/min

It's pretty clear that Spamassassin, Bayes and RBL are each pretty serious CPU hogs, but RBL is more network I/O bound than CPU bound.

I'm pretty tired of those spammer bastards cutting my communication lines (a subject most Scientologists feel strongly about, as communication is pretty much the most core element in Scientology), so I'm definitely looking for creative ways to process mail fast, but also more effectively. Comments welcome!