The SeaMonkey project is a community effort to develop an all-in-one Internet application suite. It contains an Internet browser, email and newsgroup client with an included Web feed reader, HTML editor, IRC chat, and Web development tools, and is sure to appeal to advanced users, Web developers, and corporate users. It uses much of the Mozilla source code powering such successful siblings as Firefox, Thunderbird, Camino, Sunbird, and Miro.
centericq is a text mode menu- and window-driven IM interface that supports the ICQ2000, Yahoo!, AIM, IRC, MSN, Gadu-Gadu, and Jabber protocols. It allows you to send, receive, and forward messages, URLs, SMSes (both through the ICQ server and email gateways supported by Mirabilis), contacts, and email express messages, and it has many other useful features. An internal RSS reader and a LiveJournal client are also provided.
BZFlag is a 3D, multiplayer, tank battle zone, capture the flag game that pits players against each other in a networked environment. It runs on Windows 95/98/NT/2000, Linux, MacOS 10.x, Irix, Solaris, and others. An OpenGL accelerator is highly recommended, but it is playable with 3D in software.
BitlBee allows users to talk to people on the major instant messaging and microblogging networks (including MSN, Google Talk, AIM, and Twitter) from within any IRC client by emulating an IRC server. Virtual channels are created with all of the user's contacts in them, who can be talked to in the channel or in a query. Also, one can participate in group chats and chat rooms like they were normal IRC channels.
BitchX is the premiere IRC (Internet Relay Chat) client. It originally was a modified version of the popular ircII client, and the features were eventually merged into the EPIC IRC client. The current development is aimed at merging the client back to a current branch of EPIC and bringing compatibility and stability back to the client, while bringing the features that are BitchX into a new client.
jabberd is a Jabber/XMPP instant messaging server. It implements XMPP-Core (RFC3920), XMPP-IM (RFC3921), and a range of protocol extensions: XEP-0012, XEP-0016, XEP-0030, XEP-0049, XEP-0054, XEP-0077, XEP-0079, XEP-0092, XEP-0114, XEP-0138, XEP-0153, XEP-0157, XEP-0160, XEP-0191, XEP-0192, XEP-0193, XEP-0198, XEP-0199, XEP-0202, XEP-0203.
123 Flash Chat Server is a full-featured chat server for high-load Web sites. It features a range of customization options, and can be smoothly integrated with the database of almost all leading CMS or forum systems including Joomla!, phpBB, skadate, and vBulletin. It includes plain text chat and video chat options, and is scalable enough to fit the needs of small business and large enterprises. A free 10-user edition is available. It's based on a Java server and a Flash client, but also has various alternative clients based on technologies such as HTML/AJAX, so it can run on many platforms, including iPhone and iPad. It features avatars, smilies, Flash emotions, voice messages, entering multiple rooms, dynamic skins, loading external avatars and profiles, and a media player. The HTML 5 client significantly improves the chat performance in terms of loading speed, video layout, and user interface.
Soulseek (http://www.slsknet.org) is a communication and file-sharing system. It is quite similar to Napster: it lets you exchange files, search for files, chat with other users in public and in private, browse their files, and get recommendations for music. SoulSeek for Linux is a GUI client for the system written in Python/wxPython. It includes all the major functionality: chat, searches, and file transfers.
ngIRCd is a portable IRC daemon written from scratch. It is easy to configure, supports server links (even with original ircds) and runs on hosts with changing IP addresses (such as dial-in networks). Currently supported platforms are AIX, A/UX, Darwin/Mac OS X, FreeBSD, HP-UX, IRIX, Linux, NetBSD, SunOS/Solaris, and Windows with Cygwin.