Twisted is an event-based framework for Internet applications. It includes a Web server, an SMTP/POP3 server, a telnet server, an SSH server, an IRC server, a DNS server, a generic client/server pair for remote object access (Perspective Broker), and APIs for creating new protocols. It supports integration with GTK+, GTK+ 2, Qt, Tkinter, wxPython, Mac OS X (PyObjC) and Win32 event loops. It also supports TCP, SSL and TLS, UDP, Unix sockets, multicast, and serial ports. Supported protocols include HTTP, FTP, SMTP, POP3, IMAP, TOC, OSCAR (AIM and ICQ), SSH, DNS, IRC, NNTP, Jabber, SOCKSv4, Telnet, SIP (for VoIP), and XML-RPC and SOAP using external packages. Most protocols are supported as both servers and clients.
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.
python-jabberbot is a Jabber bot framework for Python that makes it easy to write simple Jabber bots. One can use these Jabber bots to provide information about running systems, to make Web sites interact with Jabber-enabled visitors, or notify the bot owner about updates or changes that are monitored with custom Python scripts.
GYach Enhanced is a feature-rich, improved version of the original Gyach. It is the first Yahoo! client for Linux with voice chat capabilities. It offers almost all of the features you would expect to find in the official Windows Yahoo! client. The program offers support for chat, conferences, buddy lists, and My Yahoo content. In addition, Gyach Enhanced offers many features not available in the official Yahoo! clients for Windows, Mac, and Linux. Webcam support is under development and planned for the future. Unlike the original Gyach, GYach Enhanced is designed for Linux only.
Supybot is a clearly-written Python IRC framework and bot, intended to be both easily extensible and very flexible. Several modules are included by default. Numerous plugins are already written, including Google, Factoids, RSS, Quotes, and Relay. Plugins and their commands achieve greater utility via command nesting, something that no other IRC bot does. The user database is based on "capabilities" rather than obscure flags or arbitrary numeric "userlevels", giving the bot flexibility and fine-grained control (think ACLs vs. standard *nix permissions). Developing your own additions to the bot is simple with the base classes provided; writing a new command for the bot is as simple as writing a function. Unlike many other IRC frameworks, this simplicity is achieved at no cost to generality, which lets new programmers and old programmers alike feel at home in the framework.
Akeni LAN messenger is a cross-platform instant messenger client. It is a P2P program that works on your LAN without the need of an Internet connection or a dedicated server. The client has an user interface similar to AIM, ICQ, or MSN Messenger. It supports all the standard IM features such as chat, group conference, presence management, file transfer, and emergency alert/notification. Extra features include contact management and optional tabbed chat sessions.