Pidgin

Empathy is a messaging program which supports text, voice, and video chat and file transfers over many different protocols. You can tell it about your accounts on all those services …

Psi is an instant messaging application for Windows, Linux, and Mac OS X that connects to the free, open Jabber IM network (also known as XMPP). Localized versions of Psi …

The goal of Gajim is to provide a full featured and easy to use Jabber client. Gajim works nicely with GNOME, but does not require it to run. It is …

Instantbird is an instant messaging client based on Mozilla XULRunner and the open source library libpurple created by the software developers of Pidgin. Instantbird is free software available under the …

Psi+ is a development branch of Psi IM XMPP/Jabber client. Psi is a cross-platform powerful XMPP/Jabber client (Qt, C++) designed for the Jabber power users.

WeeChat is a fast, light and extensible chat client. It runs on many platforms (including Linux, BSD and Mac OS). WeeChat is: - modular: a lightweight core with plugins around …

Spark is an Open Source, cross-platform IM client optimized for businesses and organizations. It features built-in support for group chat, telephony integration, and strong security. It also offers a great...

A beautiful, free, easy-to-use chat (instant messaging) application for the XMPP protocol (Jabber, Google Talk). Project has been discontinued, though source code is still available on website

Crossplatform Jabber client. The core program is just a plugin loader - all functionality is made available via plugins. This enforces modularity and ensures well defined component interaction via interfaces.