The d command runs a command in the background and redirects its output to a file. The output file is annotated with start and end time, the actual command used, cwd, host, etc. You can ask the d command to extract the last command from the output file and run it again, you can ask it to append to the file or not, and other goodies. It comes with handy little programs to look at the output, tail it, etc. It is sort of trivial, but has been streamlined over many years.
HAVEGE (HArdware Volatile Entropy Gathering and Expansion) is a user-level software unpredictable random number generator for general-purpose computers that exploits modifications of the internal volatile hardware states as a source of uncertainty. It combines on-the-fly hardware volatile entropy gathering with pseudo-random number generation. The internal state includes thousands of internal volatile hardware states and is merely unmonitorable. It can support several hundreds of megabits per second on current workstations and PCs.
Nutch is highly scalable Web searching software which builds on top of Apache Hadoop and Lucene Java. Key features include a Web crawler, indexer, crawl management tools, parsers for HTML, PDF, DOC, and several other document formats, and an expandable architecture that allows you to plug in additional functionality such as document parsers, custom scoring algorithms, custom content parsers, protocols, and more.
Autodia is a command line Perl application that generates UML class diagrams from source code, SQL, and database connections. It supports multiple programming languages including SQL, and can output images (using GraphViz/VCG/SpringGraph), Dia XML and Umbrello XML, or custom formats using templates.
ibistools is a small set of command-line tools that aid a PCB designer working with IBIS models. It currently consists of a full IBIS v4.1 parser and an IBIS to SPICE translator. IBIS (I/O Buffer Information Specification) is a standard, human-readable, machine-readable format for publishing IC specifications.
Herrie is a command line music player. It has a split-screen file manager and playlist interface and supports a number of file formats (MP3, Ogg Vorbis, wave, FLAC, etc). It also has some nice features, including a chroot() function for untrusted setups (remote logins, parties, etc). AudioScrobbler is also implemented using Curl.
Trans (short for Transmuter Programming Language) is an extremely dynamic, biologically-inspired prototyping language providing a framework for experimenting with naturally evolving systems of objects over the net, and for exploring new ideas about recombinant software, code morphing, and evolutionary programming. Trans is also a very capable general-purpose programming language. It's fast, flexible, compact, object-oriented, highly extensible, and easy-to-learn. It can be used for rapid prototyping, or as a scripting language, an embedded language, a network server or client, a system of cooperating network nodes, a real-time control and monitoring system, and more.