SpamPal is a mail classification program that can help separate your spam from the mail you really want to read.
SpamPal sits between your email program and your mailbox, checking your email as you retrieve it. Any email messages that SpamPal considers to be spam will be tagged with a special header; you simply configure your email client to filter anything with this header into a separate folder and your spam won't be mixed up with the rest of your email anymore!
Features DNSBL checking, White/Black lists, Bayesian filtering plugin, Regular Expression Pluging and much more!
Mail PassView is a small password-recovery tool that reveals the passwords and other account details for all popular email clients. Portable version also available.
Mozilla Thunderbird for Windows, Linux, and Mac is a free cross-platform email application that's easy to set up and customize - and it's loaded with great features. A portable version is also available.
Mozilla Thunderbird for Windows, Linux, and Mac makes emailing safer, faster, and easier than ever with intelligent spam filters, a built-in spell checker, extension support, and much more. A portable version is also available.
Mozilla Thunderbird Portable (Legacy) for Windows makes emailing safer, faster, and easier than ever with intelligent spam filters, a built-in spell checker, extension support, and much more. Also available here as an installer.