MUSCLE (Multi User Server Client Linking Environment) is an N-way messaging server and networking API. It includes client-side networking APIs for various languages, including C, C++, C#, Delphi, Java, and Python. MUSCLE lets programs communicate over a network via streams of serialized Message objects. The included server program ("muscled") lets its clients message each other and store information in its server-side hierarchical database. The database supports flexible queries via hierarchical wildcarding, and "live" updates via a subscription mechanism.
Tor is a network of virtual tunnels that allows people and groups to improve their privacy and security on the Internet. It also enables software developers to create new communication tools with built-in privacy features. It provides the foundation for a range of applications that allow organizations and individuals to share information over public networks without compromising their privacy. Individuals can use it to keep remote Websites from tracking them and their family members. They can also use it to connect to resources such as news sites or instant messaging services that are blocked by their local Internet service providers (ISPs).
Amber sits in the tcpserver chain for qmail and implements an "amber list" for incoming mail. This neither accepts nor rejects connections, but implements a number of timing-related tricks to fake out spam and virus software that doesn't implement SMTP correctly. For example, it can defer requests from new IP addresses for a few minutes before it starts passing connections on to smtpd, pause and check for programs that send data before the HELO, and otherwise make things rough for bandit bulk mailers.
Wumi is a sendmail milter using the py-milter. It rejects mail containing certain (configurable) attachment filenames (.exe, .pif, etc.) or containing a virus (checked by calling a single-user license command line scanner) by answering the SMTP DATA step with "554 5.7.1". This way, the mail server does not have to generate senseless bounces.
cerberus is a modular and robust network operator and drone monitoring service designed to protect IRC networks from common threats that plague the community. It uses a BIND9-style configuration file with a mix of Perl syntax. It includes a map module that displays a server map along with basic information, stats/protocol for core protocol support, sql, an interface to DBI, modcontrol for controlling modules in use via IRC, login, operlist for displaying a list of all operators on the network, and more. It was designed for use with pure TS6 networks such as ircd-ratbox and ircd-hybrid.