conexus is a generalized C++ I/O library that includes network support for IPv4 and IPv6 sockets, serial/TTY communications, kernel message queues, pipes, and files. Objects use sigc++ for signaling property changes and other information. Sub-libraries include conexus-gtkmm (provides a set of gtkmm widgets), conexus-dbus (provides dbus support for endpoints), conexus-nspr (provides NSPR endpoints), conexus-nss (provides NSS endpoints), and conexus-ssl (provides OpenSSL endpoints).
SpamCheetah is a network-level spam filtering solution built around OpenBSD greylisting, tarpit, and blacklisting. It comes with a Web interface and requires zero administration. It does not allow spam to even land in your network, thus saving you precious bandwidth. It does not have the 'false positives' problem of losing legitimate mail.
sshh is a set of two daemons that allows you to maintain a TCP connection if all you have available is an HTTP proxy. It is similar in functionality to httptunnel, but has a few more features. Once you have it set up, sshh will allow you to make connections forward through the proxy or backwards through it, so you can open connections in either direction.
cra2tcp converts C-array files of TCP sessions into packet captures. Windows and Linux versions are available (both in CLI mode). A C-array file contains the data of a TCP connection without the Ethernet, IP, and TCP headers. It can be created using right-click on any TCP connection in Wireshark -> Follow TCP Stream -> C Array.
nioReactor is a framework for quickly building scalable event-driven network applications. It is built on top of the Reactor design pattern using NIO sockets. This provides high performance and allows for a complete separation from the application specific code. The goal of the project is to provide a simple set of APIs that allow users to build scalable servers without needing to deal with with the cumbersome and sometimes temperamental peaces of the NIO package.
Ding is a PHP framework that provides dependency injection (by Setter, Constructor, and Method), Aspect Oriented Programming, XML, YAML, Events support, and some JSR 250/330 annotations as bean definition providers, lightweight, can be deployed as a PHAR file, simple, and quick MVC, syslog, TCP client and server with non-blocking sockets, timers, and custom error, signal, and exception handling, PAGI integration (for the Asterisk gateway interface), and PAMI integration (for Asterisk management). It is similar to Java's Seasar and Spring.