Adiumx IM Application for MAC OS X

Adium is a downloadable free instant messaging application for Mac OS X, released under the GNU GPL and developed by the Adium team. With Adium, you can connect to any number of messaging accounts on any combination of supported messaging services and then chat with other people using those services.
Supported services are AOL, Jabber, MSN, Yahoo Messenger, Bonjour, MySpace IM, Gadu-Gadu, Novell Groupwise, QQ and Lotus Sametime. It features OTR encryption, tabbed messaging, file transfer and webkit message display.