Ever worried about spam problem. We all do. Now no more, with SpamAssassin spam filter, which is available at your mouse-clicks. SpamAssassin is using a bayesian filter, which automatically learn all of your spam emails, and filter that out in the future. In the spamAssassin configuration page, you will have the options to set a spam level at which all spam emails will be blocked and auto-deleted.
You can also configure a whitelist, where all email from certain domains will be whitelisted. You will not have any missing emails anymore.
Check out the screenshots below: