ADIUM!!, I’v been using adium since 2009.
It’s awesome. I use adium to ‘visit’ some of my old friends of IRC network PTNET.org.
This is the theme that I use… remembering the old times of mIRC!

https://github.com/jakebellacera/coder-theme

http://xtras.adium.im/index.php?a=xtras&xtra_id=8421