HydraIRC is an open-source IRC client with an attractive and easy to use interface. It supports DCC Chat and File transfers, Connecting to multiple servers, Dockable Floating Tabbed Windows, Autohiding Windows, DLL Plugins, Channel Monitoring, Message Logs, Event Viewer, Themes, Color schemes, Buddy groups, Audible and Visual Notifications , Reg-Exp Highlighting, Favorites and much more.
Note: HydraIRC is NOT a script, plugin or any other kind of add-on for mIRC. In fact it's got nothing to do with mIRC at all.

Features:
* Written in C++ using modern tools (Visual Studio 7)
* Uses WTL/ATL for a Super fast, streamlined and efficient program!
* Uses XML for all config files, very minimal registry usage
* Dockable tabbed auto-hidable windows, tabbed MDI client area.
* Event based core (with user definable events)
* Nice looking, intuitive GUI, no skinnable ugly rubbish.
* Supports connecting to an unlimited number of servers
* Reliable server/network reconnects
* Supports private messages and Query windows
* Supports DCC chat and File transfer
* DCC File resumes with rollback and same-file checking.
* Nick Completion (in Server, Channel, DCC and Query windows!)
* FServe functions built in (e.g. auto-requeue on disconnect + more)
* User identities (username, nick list, etc) can be assigned on a per-server/per-network basis
* A user profile can store multiple identities.
* Highlighting can trigger events.
* Audio Mute function!
* Command profiles (a bunch of commands that are given to be run one after the other)
* Auto-Connect on startup list lets you connect to multiple servers on startup
* Auto Connect Command profiles can be attached on a per-server/per-network
* Auto Join Command profiles can be attach to channels on a per-network basis.
* User list icons denoting ops/voice, etc.
* Remembers nicks on a per-server or per-network basis, can auto-update the user profile automatically.
* Supports all known text style codes (colors, italics, bold, underline, etc)
* Supports changing fonts via control codes
* Toggleable channel userlists with additional dockable user list that shows the current channels users
* DLL Plugin SDK.
* Scripting via way of DLL Plugins. (You can make plugins that can run scripts written in any scripting language!)

The license of this software is Freeware, you can free download and free use this irc client software.