KMess is an MSN Messenger/Windows Live Messenger client, made for KDE.
It supports fast file transfers, display picture transfers, custom emoticons, customizable chat styles, winks, handwritten messages, offline messages, and much more.
The latest released version for KDE3 is 1.5.2. It is the last one for KDE3, since it has been discontinued.
The new KDE4 version, with an incredible amount of improvements on 1.5.2, is about to be released (as of april 2009) in pre-release version Beta 2.
It runs on any KDE4-supported platform.