Does anyone have any experience with Active Spam Killer or other active whitelist software or service? I'm getting to the point where I'm ready to try a more active approach to combatting Spam. Spamassassin seems to need a lot of babysitting, at least how I have it set up, and is usually only blocking 80% of Spam for me. I prefer software to a service simply because I'm prone to managing my own server. I'm open to suggestions.