This is the type of product that makes you scratch your head wondering whether it was worth the purchase or not. It really doesn't add much beyond the normal filtering capabilities of MS Outlook or Outlook Express. You have to invest the time to set up rules for filtering in order to make it halfway decent. There's nothing to distinguish it from the plethora of other anti-spam software out there. McAfee recently purchased the rights to a competing anti-spam product, which many feel is a superior product (Spam Assassin). Hopefully they will use the technology to improve on Spamkiller in the future.