SOGo Zero-Effort-Groupware
Strong Email & Apache Log Analysis with Active Security Features
Google Apps Script to send third party recruiter email to spam
Full SMTP/Mail server Appliance in 5 minutes
Business webmail modular application with mobile client
Multiple account (or label) Gmail notifier (without storing passwords)
Send private e-mails through Gmail.
A faster version of Xoops optmized for speed