0MQ is a lightweight messaging kernel. It achieves 25 microsecond end-to-end latencies and 2.8 million messages per second. It is intended to be fully AMQP-compliant.
BitlBee is an IRC to other chat networks gateway. Read more
BuddyPress is an open source social networking software package. It is a powerful plugin that takes a WordPress.org powered site and transforms it into social network platform with features including user profiles, activity streams, and user groups. Read more
Community Builder is a popular open source social networking solution that offers the tools and usability needed to grow and maintain a website community. Read more
Dianara is a client for the Diaspora social network. It allows users to manage their Diaspora social network accounts without using a Web browser.
Drupal Commons is a Drupal distribution from Acquia. It is a ready-to-use open source solution for creating both internal and/or external communities. It offers a complete social business software solution for organizations. Read more
Elgg is a highly respected open source social networking framework. It provides the necessary functionality to allow you to run your own social networking site, whether publicly (like Facebook) or internally on a networked intranet (like Microsoft Sharepoint). Read more
Interverse is the evolution and combination of the Web, chat, instant messaging (IM), and voice communication.
Kommuni-K is a complete communication system. It gathers many funtions into one single modularized client/server system : - Instant messaging (ICQ - like) - Chatrooms - Global file sharing (napster-like) - Bookmark sharing - GUI to netsoul.
linc is not cyberoam
linc is not cyberoam is a free multiplatform client for Cyberoam and 24online. Cyberoam is an employee internet management system used by corporate networks. 24online is a software that implements user access, authentication and accounting for broadband ISPs
Newebe is a distributed social network
Oxwall is a free open source software package PHP/MySQL social networking software platform for building social networks, family sites and collaboration systems. It is a flexible community website engine developed with the aim to provide people with a well-coded, user-friendly software platform for social needs. It is easy to set up, configure and manage Oxwall. Read more
Secure Internet Live Conferencing: a protocol which provides secure conferencing services in the Internet over insecure channel
VOCP is a complete voice messaging solution, featuring voicemail boxes, email pagers and DTMF command shells.
Xfriends is a buddy list program for X11 / Qt. It uses fingerd, so your buddies need not run Xfriends.