DarkFire IRCd is an efficient, modern, and flexible IRC server used primarily on the DarkFire IRC Network. Originally based on Dreamforge, it has numerous enhancements and a wider variety of features. It features an efficient server to server protocol, a wide variety of user and operator commands, and a flexible protocol.
Datasphere is a conferencing system that was designed to overcome some of IRC's largest problems (scalability, no mesh routing, flat channel structure). It provides a usenet-news-like channel structure, a TCP level multicast implementation over a mesh of TCP links, a distributed channel- and user database and much more features. But most important of all. it's IRC compatible at the client side. Currently basic chatting functionality works, dynamic rerouting works, but progress is very slow.
dircproxy is an IRC proxy server ("bouncer") designed for people who use IRC from lots of different workstations or clients, but wish to remain connected and see what they missed while they were away. You connect to IRC through dircproxy, and it keeps you connected to the server, even after you detach your client from it. While you're detached, it logs channel and private messages as well as important events, and when you reattach it'll download those logs to you using ordinary IRC protocol.
DreamBot is an experimental IRC bot totally written in Perl. Its main features include a totally dynamic user and channel list (no need to deal with text files), a learning ability that's similiar to infobot, built-in seen and topten talkers support, notes/memos, pasting of Freshmeat and Slashdot news, and Babelfish (Altavista) translation. DreamBot doesn't require any extra Perl modules.