SILC (Secure Internet Live Conferencing) is a protocol which provides secure conferencing services in the Internet. It can be used to send any kind of messages, in addition to normal text messages. This includes multimedia messages like images, video, and audio stream. All messages in the SILC network are encrypted and authenticated, and messages can also be digitally signed. SILC protocol supports AES, SHA-1, PKCS#1, PKCS#3, X.509, OpenPGP, and is being developed in the IETF. The software is delivered as SILC Client for end users, SILC Server for system administrators, and SILC Toolkit for application developers.
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.
PPhone is a universal communication client for IP telephony and instant messaging. The application's design is modular, so GUI, protocol, codec, and sound drivers have plugin interfaces, the GUI is detachable, and you can switch among different GUI implementations and change the client's configuration at runtime. With the gaimhack module, you can use IM plugins from Gaim 2 to access mainstream IM networks.
Atheme IRC Services is a portable, secure set of IRC services that are designed to run on many IRCds. Unlike alternative packages, its core is minimalistic, providing only required functionality. Extra modules that provide functionality you want as a network administrator can be acquired through a module repository. It provides a fairly complete services set, excluding features designed for oper abuse. It also adds a twist on many of the classic features of Services, such as NOOP.