NetPlug is an extensible multi-connections, multi-protocol, network client program, written in pure Tcl/Tk. Includes a complete Irc client plug in that you should love if you like IrcII 'classic' look & feel (plus customizable style/colors scheme, sound,... Now includes full DCC support (with GUI), ircII like aliases and improved scripting (Tcl!), keywords (your nick...) highlighting, and more
OpenVerse is similar to other graphical chat systems like Excite Chat and Microsoft Chat, with the main differences being that OpenVerse is open source software, has no advertisements, and also runs on a variety of systems including Windows, Unix, Macintosh, and just about anything else for which you can find a copy of TCL/TK.
Trebuchet Tk is a MUCK/MUSH/MOO GUI client written entirely in TCL/Tk. It supports both Unix/X11 and Windows, and includes powerful scripting, triggers, hilites, macros, quickbuttons, keybinds, etc. that you would expect from a good MU* client. It also supports MCP simple-edit, and GUI dialog packages for MOO and FBMUCK6. For Muck users, Trebuchet also supports intelligent colored editing of MUF and MPI programs.
savIRC is an IRC client for Linux, Unix, BSD, and Windows. It supports multiple server connections, SOCKS5 proxy, CTCP, DCC, passive DCC, ignore and notify lists, Unicode, mIRC colors, MDI dedicated windows, logs, customizable popups, pre-defined events, scripting in Tcl/Tk, captions for URL nicks, and channel names.
IRK is a Tcl IRC client library. IRK is intended for Tcl programmers that want to use the IRC protocol for communication. It can be used to ease the creation of IRC "bots", to serve as the basis for graphical chat clients, and to allow IRKs to find each other without centralized coordination by meeting on a designated IRC server and channel. This last feature makes it ideal for negotiating the initial contact of P2P programs without requiring a central registry or server.
The Tcl IRCd is a small IRC server written in Tcl. It is very simple to modify. It is not a full implementation of the IRC protocol, but it's enough to create channels, talk in public or private, change topic, nick, and other basic operations. No configuration is required. The server is designed so that it can reload an updated version of itself at runtime without closing client connections.