Twiggi Web Based Groupware is a Web based groupware application, written in PHP4, using MySQL as its database engine. It was originally based on the excellent TWIG project. With many on-going enhancements, it is similar to Microsoft Outlook, and features the following modules: twiggi today, Mail, Contacts, Notes, ToDo, Bookmarks, and extensive online help (available in English and German). Twiggi has full language support for German, Dutch, Italian, and English.
Address Book Server allows you to share your contacts and calendar events with others connected to your network or over the Internet. Each participant synchronizes their contacts with the server hosted on your own system. Address Book Server supports the full Address Book and iCal schema. The server also provides a friendly Web interface and an iPhone client which let you access your contact details remotely.
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.
Akeni Instant Messaging Server Pro is a client/server instant messaging platform that allows companies to host their own secured private IM system. The client has an user interface similar to AIM, ICQ, or MSN Messenger. It supports all the standard IM features such as chat, group conference, presence management, file transfer, offline messages, and emergency alert/notification. Extra features include contact management and optional tabbed chat sessions. The server has advanced administration tools for managing user accounts, client-side logging capabilities, and peer-to-peer file transfers. It can be set up on a private network without connecting to the Internet, and can easily be set up for use inside and outside of the company firewall.