What are some alternatives?
Mailwasher - Over 8 million people use MailWasher as their spam filter
Spam Reader - Spam Reader is a free anti-spam add-on for Microsoft Outlook.
SpamSieve - Save time by adding powerful spam filtering to the e-mail client on your Mac.
POPFile - POPFile classifies email into categories you define.
SpamAssassin - Use this program to "Unspam" your mailbox(es).
BullGuard Spamfilter - Most people find spam e-mails the biggest nuisance on the Internet.