ANT 4 MailChecking   
http://ant4.com

ANT 4 MailChecking is an e-mail checker that lets you know when you have new email messages. It's very easy to set up and use and even includes support for spam filtering. It allows you to set up as many separate accounts as you like and checks for new messages at a regular interval of your choosing. A tiny window (optionally always-on-top) remains on your desktop, displaying the number of messages waiting for you on your server. You can hide the window, if you prefer, in favor of audio notification. ANT 4 MailChecking also allows you to set up a variety of spam filtering rules, based on sender, subject, message size and date. You can preview mails, assign custom icons, and delete them directly from the server. You can even shutdown your PC by email.

TabMail   
http://dlg.krakow.pl

TabMail for Windows (95/98/Me/NT/2000/XP) is mail user agent (MUA) for sending, receiving and managing your email messages. It's small and fast, conforms Internet Standards and supports Unicode characters. Some other properties: * Automatic attachments compression with zlib library * Warn when open (or save) dangerous attachments * Message filtering (input and output) using regexp TRE library * Spam filtering using SpamBayes message header additions * Simple view of compound messages * Message-thread can span many mailboxes * HTML messages view as plain text (see htmlp for more details). * Easy PGP message encryption/decryption * SMTP and POP3 authentication * Support for SSL/TLS connections * Scanning attachments for viruses * Multi-user and multi-account * Tracing for diagnosing TCP, POP3, SMTP or filter errors

PopScan   
http://www.firstsolo.net

PopScan is an efficient little shareware app that will check for new e-mail waiting to be collected from your POP3 mailboxes. Features include: Install and uninstall support; Evaluation version fully functional; Checks multiple mailboxes; Small footprint; Spam filter with heuristical spam detection; Highly customisable; Supports multiple users on one PC; Runs as a system tray utility; Windows 95/98/NT/2000/ME/XP; Online Registration PopScan is design to be small and inconspicuous and yet easy to use and richly featured. With this in mind, the author encourages users to contact him with ideas and suggestions. The result is a mature software product that meets the needs of its users. PopScan is distributed as Shareware, allowing you to download it and evaluate it for 30 days before deciding whether to purchase a license for it.

MDaemon   
http://www.altn.com

MDaemon , Windows-based email server software, contains full mail server functionality and control with a strong emphasis on security to protect your email communication needs. MDaemon features include top-notch antispam security features; seamless integration with AntiVirus for MDaemon plug-in; built-in groupware functionalities for sharing folders, tasks, contacts, and address; separately licensed plug-in for Outlook users to access groupware functionalities using MDaemon as the mail server and groupware platform; secure instant messaging; free web-based email client; remote administration tool; central address book repository; and much more! MDaemon 8.1 new feature includes the first implementation of DomainKeys Identified Mail (DKIM) for the Microsoft Windows platform. DKIM validates the sender address and message integrity of each email received. MDaemon creates outbound signatures and validates inbound messages signed with DKIM. Read Alt-N's published white paper on DKIM and its implementation in MDaemon at http://www.altn.com/support/white_papers.asp. In addition to DKIM, MDaemon 8.1 includes support for Greylisting, a relatively new spam fighting technique which involves deferring the initial acceptance of a new mail message from unknown senders and tells the sending email server to try again later. When the sending server tries a second time - which most spam sources will not do - MDaemon will accept it. Exception options and white lists can exempt trusted senders from greylist processing. MDaemon 8.1 builds on the groupware, security and administrative improvements made available with MDaemon 8.0. MDaemon now includes free groupware functions, including shared calendars, contacts and task lists. It also continues to lead the industry in email security, professional fine-tuning and beginner ease of use.

JBMail   
http://www.pc-tools.net

JBMail is a compact and portable secure e-mail client that supports SSL/TLS encrypted POP3 and SMTP. The software has been designed for simplicity, security and on-line mailbox access meaning that mail is manipulated remotely and NOT stored locally. Delete spam or large attachments without having to first download them! This portable software does not require installation, registry keys or even temporary files. JBMail can be run from a CD or floppy disk, yet it has all the essential mail client features including attachment support, advanced junk filtering, address books, and defenses against destructive attachments. It is naturally immune to HTML and scripting attacks. With its secure design, small size, and SSL support this client is ideal for the road warrior or security-conscious remote mail user.