NOCC is a simple and fast Web-based e-mail reader which can handle POP3, SMTP, and IMAP servers. It is written with PHP5, and uses sessions, has low requirements (no database, frames), and is easy to install. It also features multi-language support, MIME attachment decoding/encoding, and the ability to display HTML messages.
NS WebMail offers standard mail functions for POP3 inbox management. Mail is sent using SMTP protocol. It has been designed to be light and simple, to avoid having to use heavy IMAP or SQL servers, and it has full MIME support for incoming and outgoing mail. It is Perl-strict and mod_perl-compliant, and has security using HTTP authentication or cookies. LDAP connectors are also available (as optional plug-ins) for authentication and read-only address book. Two interfaces are available (with and without frames). It is able to recognize tags from spam detection software (Spamassassin is supported out of the box).
oMail-webmail is a Webmail solution for mail servers based on qmail and optionally vmailmgr or vpopmail. The mail is read directly from maildirs on the hard disk, which is much quicker than using protocols like POP3 or IMAP. Other features includes multiple language support (English, French, German, Japanese, Chinese, and many more), HTML and pictures inline display, folders, and address book support.
phpGroupWare (formerly known as webdistro) is a multi-user groupware suite written in PHP. Its provides a Web-based calendar, todo-list, addressbook, email, news headlines, and a file manager. The calendar supports repeating events. The email system supports inline graphics and file attachments. The system as a whole supports user preferences, themes, user permissions, multi-language support, an advanced API, and user groups.
PHPwebmail is a Web-based IMAP and SMTP mail client. Often it is not possible to make outside mail connections from networks behind strict firewalls, or to configure a regular mail client (for example in an Internet cafe). With PHPwebmail a mail client only needs a WWW connection to the mailserver. Specifically it only needs a connection to the webserver hosting PHPwebmail. Most of the times the Web and mail server will be the same machine but PHPwebmail can connect to other mailservers as well as long as an IMAP connection between these two machines is allowed.
Postaci (Turkish for Postman) is multiplatform Webmail software which is database independent, multilanguage, POP3/IMAP, and fully MIME-compatible. While using POP3 mode to fetch messages it uses database fields to simulate IMAP folders, on which you can save, move, delete, and read e-mail. It also contains an adressbook, a notebook, and a bookmark manager application.
Pronto! is a full-featured mail client written in Perl/GTK+, and a continuation of the development of CSCMail project in Perl. It supports multiple POP3/maildir and mbox accounts, imports/exports MBOX, and has full search features and VFolders, sortable filters, threaded message list, a nested folder list, drag and drop, and inbound and outbound attachments.