ICQ

Miranda IM is the smaller, faster, easier instant messenger with support for multiple protocols. Designed from the ground-up to be resource efficient while still providing a rich feature set, Miranda …

Meebo is integrated, all-in-one instant messaging (IM client) that connects you with your friends everywhere. It supports a large number of popular servicesand connects you to MSN, Yahoo, AOL/AIM, MySpace, …

Imo instant messenger is a web-based service with video and voice chat functionality. imo's web messenger and mobile messenger apps let you IM your friends with AIM, Facebook, Google Talk, …

Kopete is an instant messenger supporting AIM, ICQ, MSN, Yahoo, Jabber, IRC, Gadu-Gadu, Novell GroupWise Messenger, and more. It is designed to be a flexible and extensible multi-protocol system suitable …

Miranda New Generation is a successor of a popular multi-protocol instant messaging client for Windows - Miranda IM. Very light on system resources and extremely fast.

Galaxium is an instant messenger application designed for the GNOME desktop. It will allow you to connect to MSN, Jabber, and IRC. You can communicate with your family, friends and …

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....

Check ReChat (Android messenger): http://refineandroid.doodlekit.com/ - Facebook, Yahoo!®, Google Talk, WLM/MSN, Jabber/XMPP; - group chat (Yahoo!®, Google Talk, WLM/MSN, XMPP); - free voice calls...