Pidgin, formerly 'Gaim', is a free, open source, instant messaging program for Windows, Linux, BSD, and other Unixes. You can talk to your friends using AIM, ICQ, Jabber/XMPP, MSN Messenger, Yahoo!, Bonjour, Gadu-Gadu, IRC, Novell GroupWise Messenger, QQ, Lotus Sametime, SILC, SIMPLE, and Zephyr. Pidgin supports many features of the various networks
Pidgin can log in to multiple accounts on multiple IM networks simultaneously. This means that you can be chatting with friends on AIM, talking to a friend on Yahoo Messenger, and sitting in an IRC channel all at the same time.
Pidgin runs on a number of platforms, including Windows Linux, and other UNIX operating systems.
Looking for Pidgin for OS X? Try Adium!
Portable Pidgin w/Launcher (Multilingual) can be found at winPenPack.com; PortableAppls.com also packages a Portable(Gaim)file.
Website: Pidgin IM
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