Pidgin is a universal chat client that allows users to manage multiple instant messaging (IM) accounts from a single interface. Pidgin software is free and open source.

Pidgin supports the following chat networks:    

    •    AIM
    •    Bonjour
    •    Gadu-Gadu
    •    Google Talk
    •    Groupwise
    •    ICQ
    •    IRC
    •    MSN
    •    MXit
    •    MySpaceIM
    •    SILC
    •    SIMPLE
    •    Sametime
    •    XMPP
    •    Yahoo!
    •    Zephyr

With a few quick mods, it can be used for secure chats. Find out how here!