GNU Gadu 2 is a modular instant messaging client with a GUI written in GTK2. It currently supports Gadu-Gadu, Tlen.pl, and Jabber. It is able to load Perl scripts, dock in several window managers, play sounds, talk to other programs via a UNIX socket, send SMS messages to Polish GSM operators, automatically check for updates, and use XOSD for displaying notices.
The Eggdrop Jabber Bot bridges your Eggdrop IRC bot to the Jabber instant messaging network and thus to ICQ. This code is meant to be a demo that it can be done, and a basic starting point which you can extend to your needs. The only functionality currently included is an invite feature.
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.
cerberus is a modular and robust network operator and drone monitoring service designed to protect IRC networks from common threats that plague the community. It uses a BIND9-style configuration file with a mix of Perl syntax. It includes a map module that displays a server map along with basic information, stats/protocol for core protocol support, sql, an interface to DBI, modcontrol for controlling modules in use via IRC, login, operlist for displaying a list of all operators on the network, and more. It was designed for use with pure TS6 networks such as ircd-ratbox and ircd-hybrid.