NetMail 

NetMail can store information on many e-mail accounts. If you have several external mailboxes at different ISPs you will not need to enter a new password and adjust the settings every time.
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KnockKnock 

Anti Spam program eliminates unsolicited e-mails in your inbox. KnockKnock is a complete e-mail enhancement program and spam solution, and works with your current Email client. Easy features handles, multiple e-mail accounts on multiple servers.
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Internet Drummer! 

This program allows you to preview e-mails on multiple POP3 servers and delete unwanted messages before using e-mail client. It includes automatic spam filtering and serves as a notifier for both new e-mail arrivals and changes on specified web pages
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S-Agent 

S-Mail Agent is a one-step email encryption plug-in for any email software such as MS Outlook, Eudora, Mozilla, Outlook Express, Pegasus, TheBat!, Netscape Mail, etc. Enjoy secure email via your favorite email program!
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Advanced Direct Remailer 

Powerful remailer which sends your message straight out to the recipient's mail server. Multi-threaded direct delivery, internal SMTP server, mailing lists, databases, plugins, open API, ActiveX/COM interfaces, Socks5, more.
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Spam Crusher 

Spam Crusher is designed to filter unwanted email, while allowing the email you want to receive. Spam Crusher can be configured to filter multiple email accounts. Spam Crusher is really easy to set up. In just a few minutes you can be up and running.
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