I hear so many great things about new and popular instant messaging clients developed for the Apple OS X platform. Unfortunately, like most quality open source projects, they are developed for one native platform long before any ports or complete redevelops are available.

I am somewhat displeased with the operation of the Trillian all-in-one IM client and have been for some time now. I am looking for one or more possible alternatives for the Windows platform that operate similar to Trillian, but offer it in a more lean package — much like how Trillian used to be before the architecture was re-written for the use of plug-ins and the user interface scrapped.

I would like something similar to Adiumx (recent review) or Fire. A simple, yet highly configurable multi-protocol instant messaging client that will handle the basic features associated with chatting. Additional features like peer-to-peer file transfer and video conferencing are not priorities.

Please comment with any and all suggestions.