The RegLookup project is devoted to direct analysis of Windows NT-based registry files. RegLookup provides command line tools, a C API, and a Python module for accessing registry data structures. The project has a focus on providing tools for digital forensic examiners (though it is useful for many purposes), and includes algorithms for retrieving deleted data structures from registry hives.
Lynis is an auditing and hardening tool for Unix derivatives like Linux/BSD/Solaris. It scans systems to detect software and security issues. Besides security-related information, it will also scan for general system information, installed packages, and possible configuration mistakes. The software is aimed at assisting automated auditing, software patch management, and vulnerability and malware scanning of Unix-based systems.
Yet Another Flowmeter (YAF) is a tool for network flow capture, primarily designed to operate efficiently on white box hardware and generate IPFIX flow records. It is designed to operate primarily on Unix-based systems (including Mac OS X), and is supported by the Network Situational Awareness team at CERT.
PTK is an alternative advanced interface for the TSK (The Sleuth Kit) suite. It was developed from scratch. Besides providing the functions already present in Autopsy, it implements numerous new features essential during forensic activity. PTK provides a graphical and highly professional interface based on AJAX technology. It also offers a great deal of features like analysis, search, and management of complex cases of digital investigation.
WTMParse is a script originally intended for use in forensic examinations which parses WTMP files from Unix-like operating systems and generates a CSS-styled HTML report containing the login terminal, username, log start date, and login time/date in a table. It's good for postmortem forensic examinations or as a way of getting "last"-like information when you don't have the ability to boot the machine in question but can grab the wtmp.
Gpart is a small tool which tries to guess which partitions are on a PC harddisk in case the primary partition table was damaged. It works by scanning through the device (or file) given on the commandline on a sector basis. Each guessing module is asked if it thinks a filesystem it knows about could start at a given sector. Several filesystem guessing modules are built in, and others can be added dynamically.