JabberIM.exe will allow you to connect to all of the major IM systems from a single program. Trillian does this also. More information can be found here.
Quote: Jabber is best known as "the Linux of instant messaging" -- an open,
secure, ad-free alternative to consumer IM services like AIM, ICQ, MSN,
and Yahoo (see the IM quickstart). Under the hood, Jabber is a set of streaming XML protocols
and technologies that enable any two entities on the Internet to
exchange messages, presence, and other structured information in close
to real time. Jabber technologies offer several key advantages:
Every attempt has been made to ensure the information about JabberIM.exe is accurate but alot of malware applications try to pose as valid applications. If it is something other than what was posted above please leave some feedback in the forum.