Bouncer is an IRC session manager that can share a single server connection between multiple clients. This makes it possible to run the same IRC session at home or in your office. It also has a flexible plugin structure that allows you to record message and do logging in a centralized place.
BSW IRC Proxy translates the chat aspect of the proprietary binary protocol used in the Java client for the online gaming portal BrettSpielWelt.de to the standardized features of IRC (RFC 1459, 2810, 2811, particularly 2812, and 2813). It keeps a persistent connection to the client, server, and IRC client, in case one of them should vanish.
Bip is an IRC proxy that supports replaying logged conversation and multiple clients on one IRC server connection. It has a handy logging directory structure. It is multi-user and has a flexible configuration. Some of its configuration can be changed at runtime with special IRC commands.
Quassel IRC is a modern, cross-platform, distributed IRC client, meaning that one or more clients can attach to and detach from a central core, much like the popular combination of screen and a text-based IRC client, but graphical. In addition to this unique feature, it aims to be a comfortable chatting program.