Anti-Spam Your Inbox: "While no filtering system is perfect, you can greatly reduce the number of spam and junk e-mails that you receive using your mail program's filtering function.

You may have noticed that a lot of spam does not contain your actual e-mail address in the To: field. Spammers put some bogus address in there to hide the recipient list. Your actual e-mail address is hidden in the message header. You can take the practice the spammers use and use it against them to filter out their garbage. "