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.
Dianara is a client for the Diaspora social network. It allows users to manage their Diaspora social network accounts without using a Web browser.
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
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.