VanMail   
http://www.vandaveer.com

VanMail is a powerful POP3/SMTP email client that allows you to manage your email with ease. With VanMail's powerful built-in SPAM protection, you control the emails you want to receive. VanMail comes with a powerful rules based system where you can create rules to block emails, whitelist rules (i.e. never block), auto-response rules, alert rules, etc. VanMail also comes with an advanced challenge-response system. You can even configure VanMail to encrypt your downloaded email so that others who have access to your system can't read your email.

Advanced Mailbox Password Recovery   
http://www.elcomsoft.com

A program to recover login and password information (stored locally) for most populat email clients: Microsoft Internet Mail And News, Eudora, TheBat!, Netscape Navigator/Communicator Mail, Pegasus mail, Calypso mail, FoxMail, Phoenix Mail, IncrediMail, @nyMail, QuickMail Pro, MailThem, Opera mail, Kaufman Mail Warrior. Also includes POP3 server emulator that allows to get POP3 password from ANY email client. Passwords are recovered instanly, multilingual ones are supported.

yMail   
http://www.spacejock.com

yMail can be used as a spam cleaner for your existing email setup, and also as a standalone email client. yMail's spam filters use Bayesian techniques. You can show yMail which messages are spam and which are not (before you even download them to your computer!) and each time will adjust its filters to suit. After a few days, it will be able to sort mail quickly and efficiently without any input. yMail can also be used as a mail scanner - you don't have to use the email portion of the program, just use yMail to preview and automatically delete spam before downloading into your regular email software. Free software from the author of the Hal Spacejock series.

Popp   
http://www.thejackol.com

Popp is a small and quick POP3 client that will help you manage multiple POP3 accounts, access them quickly, preview messages and delete multiple messages. It includes Rijndael encryption for passwords that are stored with it, along with support for Proxy servers. A must for users with multiple email accounts.

Mail Trustee   
http://ml-tr.com

Do you get a lot of unwanted mail in your mailbox? - Are you tired of selecting unwanted messages and wasting time on them? - Do you lose wanted messages amidst all that trash you get in your mailbox? - Do you pay extra money because your mail client receives unsolicited mail? Mail Trustee will help you solve these problems and more! Mail Trustee: a system of E-mail protection programs intended to protect your mailboxes from unsolicited mail (spam). Mail Trustee acts as a proxy server, which is situated between your mail client and mail server. Our unique technology will filter out a huge percentage of the spam, allowing minimum possible mail server access time with a minimum volume of sent and received information. Mail Trustee supports up to 255 mailboxes and each mailbox may have its individual settings for spam filtering and mail rocessing. Mail Trustee has a flexible system of settings which allows adapting it to a user's needs. An individual functioning cycle can be set up for each mailbox; it will include: - Receiving mail from mail client with further transfer to mail server - Transfer of received mail from mail server to mail client - Establishing an Internet connection if needed - Mail transfer to mail server - Mail analysis on mail server, unsolicited mail detection for decision-making (delete, accept, etc.) - Receiving mail from mail server - Interrupting an Internet connection if needed While analyzing mail, all necessary types of checks are performed, which gives an excellent result in spam filtering. The following checks may be used in the system: - Allowed E-mails - Forbidden E-mails - Allowed zones - Forbidden zones - Allowed domains - Forbidden domains - Field validity "To:" - Field validity "Received:" - Field syntax "From:" - Lists DNSBL - Allowed expressions in Subject - Forbidden expressions in Subject - Forbidden expressions in Header - Allowed expressions in Message - Forbidden expressions in Message