Textual is a lightweight IRC client created specifically for Mac OS X. It was designed with simplicity in mind. Textual has taken the best of IRC and built it into a single client. Its easy-to-use functionality combined with scripting support makes it an ideal IRC client for novice to advanced users.
Textual provides many great features:
Native fullscreen support.
Full support for IPv6 users.
Support for encrypted conversations.
Automatic SASL support. Zero setup required.
Support for new IRCv3 standards.
Support for SSL as well as SOCK proxies.
Support for client-side certificates.