Flex is a tool for generating programs that recognize lexical patterns in text. There are many applications for Flex, including writing compilers in conjunction with GNU Bison. Flex is a free implementation of the well known Lex program. It features a Lex compatibility mode, and also provides several new features such as exclusive start conditions.
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.
traffic-vis is a suite of tools to help determine which hosts have been communicating on an IP network, with whom they have been communicating and the volume of communication taking place on a host by host basis. Reports can be generated in ASCII and/or HTML format. traffic-vis can also generate Postscript(tm) and GIF charts showing which hosts have communicated with each other.
ZMailer is an internet message transfer agent. It is intended for gateways or mail servers or other large site environments that have extreme demands on the abilities of the mailer. It was motivated by the problems of the Sendmail design in such situations. It is intended and designed as a multi-protocol mailer. The only protocol supported in this distribution is RFC822 (and variations).
QuantLib is a cross-platform, quantitative finance C++ library for modeling, pricing, trading, and risk management in real-life. It is also wrapped as Python/Ruby/Scheme modules. Extensions for Excel, R, and Mathematica are available. Other such extensions are under consideration. QuantLib offers tools that are useful both for practical implementation and for advanced modeling. It features market conventions, yield curve models, solvers, PDEs, Monte Carlo (low-discrepancy included), exotic options, VAR, and so on.