aMSN
A powerful MSN (WLM) client that supports skins, plugins, system tray icons, cameras, multi-account logins, offline information, and more.
Pidgin
Needless to say, it is the IM client under GNOME that supports the aim, Google talk, ICQ, MSN, Yahoo and IRC protocols.
Empathy
is the default installed IM tool under Ubuntu, supporting Google Talk, MSN, IRC, Salut, AIM, Facebook, Yahoo, Gadu-gadu, Groupwise, ICQ and QQ. But QQ is caodan~ helpless
Kopete
is the default IM client under KDE, performing more popular protocols that support video.
Finch
Contains the Pdigin software package, which is an IM client running in text mode under the terminal, supporting all pdigin protocols.
emesene
is another MSN client. Supports cameras, tips, themes, and more.
Kmess
is an MSN client under KDE.
Ayttm
Support Jabber, MSN, Yahoo, IRC, aim and so on.
Skype
One of the most popular telephony applications, enabling instant messaging, file transfer, and camera.
Centerim
is a branch of CENTERICQ, based on the terminal, supports ICQ, Yahoo, MSN, AIM, ICQ, Jabber, IRC, Live Journal and Gadu-gadu.
If there is any good Linux under the communication method can leave a message to discuss, let everyone refer to the next.
Original link: http://www.lupaworld.com/article-209480-1.html
Summary: Linux under 10 instant Messaging clients, Skype