groupware

imap

procmail

ResendingMailWithHeaders - Spamassassin Wiki Here's how to redirect (or "bounce") a mail message to another recipient. This is important when training Bayes via mail (as described in ProcmailToForwardMail), for example. It's often critical to redirect the message, rather than forwarding. Forwarding loses all of the critical header information, which is much of what Bayes trains from. Here are directions for redirecting from different clients. ResendingMailWithHeaders - Spamassassin Wiki
Zimbra Collaboration Server (ZCS) Open Source Edition is available for you to test, evaluate, deploy, customize, and improve. In doing so, we hope you will participate in the Zimbra Community, so that we can work together to make ZCS a better product for everyone. It is free in perpetuity (providing you comply with the associated Zimbra Licensing Terms). Open Source Edition Downloads: Enterprise Messaging and Collaboration Software by Zimbra

Open Source Edition Downloads: Enterprise Messaging and Collaboration Software by Zimbra

Claws Mail - the email client that bites! Claws Mail - the email client that bites! Claws Mail is an email client (and news reader), based on GTK+, featuring Quick response Graceful, and sophisticated interface
The Email Standards Project works with email client developers and the design community to improve web standards support and accessibility in email. Our goal is to help designers understand why web standards are so important for email, while working with email client developers to ensure that emails render consistently. This is a community effort to improve the email experience for both designers and readers alike.

Home | Email Standards Project

Home | Email Standards Project
Set-up Guide to “Gmail for your Domain” on Dreamhost (Inelegant Blog)
Welcome to Postbox

Welcome to Postbox

Awesome Gmail Support* Gmail Label support makes organizing easy Dedicated Important view for high-priority messages Send and Archive your messages in just one step Add detected dates to your Google Calendar Support for Gmail keyboard shortcuts for the power user * If you don't have Gmail, no worries... because Postbox works great with any POP or IMAP email account, including Yahoo!, Hotmail, MobileMe/iCloud, AOL, Comcast, Dreamhost, Rackspace, Zimbra and many more.