mIRC - mIRC: Internet Relay Chat client
lightIRC - lightIRC is a fast, free, Flash-based IRC Client. It supports webcams with an extension!
HexChat - HexChat is a fork of XChat with bug fixes and new features.
LiveAgent - LiveAgent is a fully-featured web-based live chat and help desk software. It harnesses the power of a universal inbox, real-time live chat, built-in call center, and a robust customer service portal. Start your free 1 month trial today!
Kiwi IRC - A hand-crafted IRC client that you can enjoy. Designed to be used easily and freely.
uhChat - uhChat is a chat window software that can be integrated into any website.