Arrow is an elegant, powerful, graphical interface to electronic mail. This is not just another single window mail reader. Instead, it displays each mailbox and message in a separate window, thereby allowing one to simultaneously open as many mailboxes and view and compose as many messages as one wishes. This paradigm also allows one to drag-and-drop text between messages and organize ones mail by dragging messages between mailboxes.
BrowserExpress is a Web-based e-mail client. BrowserExpress provides a Web browser interface to any mail server, giving all your users Web-based e-mail from any Web browser. The BrowserExpress interface is fully customizable to support your branding, banner advertisements, and language choice. BrowserExpress implements POP3, SMTP, LDAP, and MIME standards.
The SeaMonkey project is a community effort to develop an all-in-one Internet application suite. It contains an Internet browser, email and newsgroup client with an included Web feed reader, HTML editor, IRC chat, and Web development tools, and is sure to appeal to advanced users, Web developers, and corporate users. It uses much of the Mozilla source code powering such successful siblings as Firefox, Thunderbird, Camino, Sunbird, and Miro.
NeoMail is a web-based email client written in Perl. It provides access to a machine's local mail spools without requiring a POP3 server to be running, and without giving users shell access. It supports sending and receiving attachments, multiple folders, user themes and preferences, templates for interface generation, quotas, language translations, etc.
SendEmail is a lightweight, completely command line-based SMTP email delivery program. If you have the need to send email from a command prompt this tool is perfect. It was designed to be used in bash scripts, Perl programs, and Web sites, but it is also quite useful in many other contexts. It is written in Perl, and is unique in that it requires no special modules, and supports any platform that runs Perl. It has a straightforward interface, making it very easy to use.
XCmail is a MIME and multi POP3 capable mailtool for X11 using the Xclasses X11 layout library. Its main purpose is to read and write mail, allowing any kind of data to be attached. It can handle MIME types, has helpers to show different types, and can encode and decode binary data into ASCII to allow it to be transported as mail over the Internet. It has many built-in functions such as 2 vCards, unlimited POP3 servers, SMTP, SMTP after POP3, SMTP-AUTH (RFC2554), addressbook, encoders, filters, a special spam filter, spell checker, xface, and a new "virtual folder" concept. It also uses external programs to enhance its feature set. XCmail can be extended through a plugin interface.
XFMail is an X11 application for receiving electronic mail. It implements most of its email functionality internally so that it does not depend on a lot of extra packages. It supports POP3, MBOX, IMAP4, sendmail, and SMTP. It has built-in support for interfacing with PGP, GPG, ispell/aspell, faces, LDAP, and esound. It runs on most Unix variants.
xP provides an intuitive, high quality, graphical (X11) user interface to the University of Washington's PINE Messaging System. xP aims to provide an interface that is welcoming and easy to use for the new user, while still retaining the look, feel and key commands of PINE for the experienced user.
NullLogic Groupware is a modular Web-based groupware and email system designed for contact management and event scheduling. Additional features include private messaging, public discussion forums, webmail, shared bookmarks, file sharing, call tracking, order processing, an XML-RPC API, and integrated POP3 and SMTP servers.
ADJE WebMail is a set of Perl CGI scripts which provide a Web interface to existing email accounts on any POP3-compliant email server. The software provides a complete interface, including encoding/decoding attachments, email and URL markup in received emails, and an address book for each user.