kicq is an ICQ client specifically designed for the KDE desktop. It has a simple, clean interface very similar to the original Windows ICQ client, and includes all of the most commonly used ICQ features such as messaging, real-time chat, and file transfer. It features complete message history, a New ICQ User registration window, multiple ICQ accounts, SOCKS5 proxy inline support, configurable sound events, Cyrillic koi8-r/cp1251 recoding, and support for the ICQ UDP v5 and ICQ TCP v2 protocols.
Pipo-BBS allows you to install a BBS server and clients. You can chat via a nice interface with an unlimited number of people (as with IRC). This software is in a pre-release state; it is still very alpha, and can be difficult to even compile. It works under linux, MkLinux, SGI, HP-UX, and Solaris. The only interface for this BBS is telnet for the moment; an interface using GTK has been started. It has been translated into French, English, Spanish and German.