newmail looks at mailboxes and determines if any new mail has arrived. The mailboxes to be examined are specified with command line arguments. A directory can be specified and newmail will check every mailbox inside. newmail is designed to be run every 15 minutes or so by a user's shell.
R-AddressBook is a Java address book which stores its data in XML format. It can be run on virtually any computer (including PDAs) and offers local and global address information storage, WebServices based synchronization, off- and on-line operation, no restriction on the type or number of fields for each entry, and automatic address updates.
Usermin For Webmail is a modified version of the Usermin package that is pre-configured for use as a Web-based email client. It is designed to work on systems running a local IMAP server, such as Dovecot. By default, users can read email, setup autoresponders and forwarding with Procmail, filter mail with simple rules, change their passwords, and manage folders.
Rspamd is an anti-spam system designed to work faster than SpamAssassin by using event model and regular expression optimization. Currently released features: regexp rules for filtering different parts of messages; a number of built-in functions for analyzing messages; fuzzy hashes support; SURBL filters; email and character tables support; a control interface for remote managing and stats gathering; a Perl and Lua plugin system; statistics support (OSB/Winnow); compatibility with SpamAssassin; and a client program for email scanning. With similar rules, rspamd is about ten times faster than SpamAssassin.