yuck is a command line option parser for C that works on a minimal set of dependencies - only a C compiler and the m4 macro processor are required. It supports all the standard use cases: GNU-style long options (--option), condensable short options (-xab for -x -a -b), and optional arguments to long and short options (--foo[=BAR]), multiple occurrence of options (-vvv). Most importantly, it does not depend on libc's getopt() nor getopt_long().
uterus is a codec library for financial tick data with an emphasis on market data integrity and maintainability. It comes with a set of tools to convert (mux) and print (demux) data from some sources, and to perform standard tasks like selecting instruments, creating snapshots and candles from tick data, etc. Special care is taken to provide longevity and consistence. All timestamps are internally converted to coordinated time, and price and quantity quotes are converted to a monetary datatype which doesn't suffer from rounding errors. Most importantly, meta data is stored along with the payload data in an inseparable unit, to provide self-contained and self-documenting files or network streams.
A tool for editing version-control repository history, reposurgeon enables risky operations that version-control systems don't want to let you do, such as editing past comments and metadata and removing commits. It works with any version control system that can export and import git fast-import streams, including git, hg, bzr, CVS, and RCS. It can also read Subversion dump files directly and can thus be used to script production of very high-quality conversions from Subversion to any supported DVCS.
Dateutils are a bunch of tools that revolve around fiddling with dates and times in the command line, with a strong focus on use cases that arise when dealing with large amounts of financial data. Their target market is shell scripts that need date calculations or calendar conversions, and as such they are highly pipe-able and modeled after their well-known cousins (e.g. dtest vs. test, or dgrep vs. grep).
ascii lists ASCII idiomatic names and octal/decimal code-point forms. It provides easy conversion between various byte representations and the American Standard Code for Information Interchange (ASCII) character table. It knows about a wide variety of hex, binary, octal, Teletype mnemonic, ISO/ECMA code point, slang names, XML entity names, and other representations. Given any one on the command line, it will try to display all others. Called with no arguments, it displays a small, handy ASCII chart.
Coq au Vin is a blogging engine written in Chicken Scheme. It is designed to appeal to users who have basic Web development skills (i.e., who know HTML and CSS), are able to install their own server-side software, and would rather edit a template than press 105 buttons to customize their sites.