Mac users interested in Limechat snow leopard generally download:
LimeChat is an IRC client for OS X written on RubyCocoa.
Lingr Radar is a tiny application that sits in your desktop and keeps track of whatevers being said on Lingr.
Lingr Radar is a fully open, easy-to-use interface for technical users to build any kind of applications using the purely web-based chat service Lingr as a realtime application platform.