Pidgin

TorChat is a peer to peer instant messenger with a completely decentralized design, built on top of Tor's location hidden services, giving you extremely strong anonymity while being very easy …

Finch is a console-based IM program that lets you sign on to AIM, Jabber, MSN, IRC, Yahoo!, and other IM networks. It runs on Unixes. It uses GLib and ncurses.

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...

Tencent QQ, generally referred to as QQ, is the most popular free instant messaging computer program in Mainland China, and has over 856.2 million users. In April 2010, QQ.com ranked …

KMess is the Live Messenger alternative for Linux, aiming at integration with the KDE desktop environment. With KMess, chatting with friends using Live Messenger has never been so good. Features: …

Tkabber is a Free and Open Source client for the Jabber instant messaging system. Its writen in Tcl/Tk, and works on many platforms (tested on Linux, FreeBSD, NetBSD, Solaris, MacOS …

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

Zoho Chat is a web based chat system. You can access it using just a web browser and an internet connection. It does not need any software to be downloaded …

Meebo for the Desktop. It uses Adobe® AIR™ to place meebo home page on the desktop in its own window.

Sim-IM is a multiple protocol instant messenger for MS Windows, GNU/Linux, FreeBSD. Sim-IM supports Jabber/XMPP, Google Talk, ICQ and AIM (Oscar), Yahoo! Messenger and Microsoft Messenger (MSN) protocols....

FBMessenger is a stand-alone Facebook Messenger app for Linux, very similar to the official Messenger for Windows. It was created by Jack O'Connor, a Facebook Developer.

ShMessenger Mobile is a free instant messaging client for mobile phones, which supports YMSG (Yahoo!), MSN and GTalk protocols. In just a few minutes, you can chat with your friends …

Subway is a web-based IRC client with a multi-user backend and a JavaScript-heavy UI. Frontend/backend communication is done with websockets (or best available fallback where not available). The backend...

Portuguese messenger publish by SAPO. It has a sending SMS feature and the user can make audio-visual calls. GTalk can be integrated with this instant messaging program.

Connect with your friends on one simple platform. Use ISIM to combine all of your contacts from Skype, Google+ and Facebook. Staying in touch has never been this easy.

Mercury Messenger or simply "MM" (formerly called dMSN) is a Windows Live Messenger network Instant Messaging client developed in Java. It supports almost all of the features in Windows Live …

pMessenger is a Cross platform Messenger (iPhone, Android, BlackBerry, and soon Nokia, WM7, Java phones) with Text/Picture/Video/Vocal/Group Chat/Image/Status updates/Acknowledgement of receipt (D/R)! ...

WeeWorld - the social network built for fun where you can meet new friends, send messages, play games, and create your own avatar. WeeWorld is an online game aimed at …

OneTeam – simple, secure and easy to use. OneTeam is a versatile instant messaging client that is very intuitive to use. Even people who are new to instant messaging will …

Facebook Chat IM is a Desktop Messenger for Facebook. With it you can chat with all your Facebook friends directly from your Desktop. It has a simple and easy to …

Minbif aims to use the libpurple library from the Pidgin project to provide an IRC-friendly instant messaging client.