Ну значит и я буду писать куда попало.
Ну вот в общем что народ пишет (мне триллиан не нравится, просто не говорить же просто что миранда только уникальна)
The most widely-used program of this genre is Trillian, which can connect to AOL Instant Messenger, ICQ, MSN Messenger, Yahoo! Messenger, IRC, Novell, Rendezvous, and Jabber. Trillian also has plugins available that gives Trillian additional features such as spell-check, weather updater, e-mail checker, winamp song title scroller, stock exchange monitor, RSS feedreader and others. The plugins themselves are free but they can only be used with the commercial version, Trillian PRO.
Other multi-protocol instant messaging clients for Windows include Miranda IM (open source) and Jabber compatible clients (Which use a program called a transport on the server side). For Linux and other Unix-like operating systems they include Kopete (KDE). For Mac OS X, clients such as Adium X, Proteus, and Fire are available. The Milkbone and Gaim (<span style='color:green'>ты вроде спрашивал еще мультипротокольных</span>) clients work on both Windows and Unix-like operating systems. Like Trillian, both Gaim and Miranda IM support feature extensions via plug-ins. Plugins for Miranda IM, Gaim and Trillian are free, however the commercial version of Trillian is required to use the Trillian plugins. Miranda IM and Gaim only offer free versions which are are compatible with their respective plugins.
<a href='http://en.wikipedia.org/wiki/Multiprotocol_instant_messaging_application' target='_blank'>http://en.wikipedia.org/wiki/Multiprotocol...ing_application</a>