Empathy project is a Gnome IM/voice/video client reusing Gossip’s UI and using Nokia’s MissionControl.
A multilanguage MSN Messenger client with file transfer support
Twisted is an event-based networking framework for Internet applications.
A lightweight twitter client for GNOME
An advanced feature-rich text conferencing system
A cross-platform voice chatting app
msn-pecan is an alternative MSN protocol plugin for libpurple
Twitim is an XMPP (Jabber-based) client for Twitter.
EZ Intranet Messenger is a messenger client for internal communication.
A Kopete protocol plugin for chatting on the MXit chat service
ZNC is an IRC bouncer with many advanced features like detaching, multiple users, multiple clients per user.
Pidgin, previously known as Gaim, is a multi-protocol instant messaging client for Linux, BSD, MacOS X, and Windows.
A client for the sushi IRC suite
PunJab is an HTTP Jabber client interface.
Konversation is a user friendly Internet Relay Chat client.
Open Source Blogging Client
cHippo reprogrammed in Java
A cross-platform (using GNOME/GTK+) IRC client software for advanced users with multiple server support.
Chat comfortably. Everywhere.
A fast and light IRC client for many operating systems.
A Free and Open Source distributed fault-tolerant Jabber/XMPP server.
IRC instant messaging gateway
