DocBook is an XML vocabulary which enables you to create document content in a presentation-neutral form that captures the logical structure of the content. Using the DocBook Project XSL stylesheets, you can publish DocBook content as HTML pages and PDF files and other formats, including man pages, HTML Help, and JavaHelp.
GNU Aspell is a spell checker designed to eventually replace Ispell. It can either be used as a library or as an independent spell checker. Its main feature is that it does a superior job of suggesting possible replacements for a misspelled word than just about any other spell checker out there for the English language. Unlike Ispell, Aspell can also easily check documents in UTF-8 without having to use a special dictionary. Aspell will also do its best to respect the current locale setting. Other advantages over Ispell include support for using multiple dictionaries at once and intelligently handling personal dictionaries when more than one Aspell process is open at once.
Frink is a calculating tool and programming language designed to help you in the real world. It tracks units of measurement throughout all calculations and ensures that answers are correct. It converts between systems of measurement, and has a huge library of physical data. It is both a simple calculator for quick calculations and a full-fledged programming language for large tasks. It draws high-quality graphics, handles conversions between time zones, currencies, and historical values of the U.S. dollar and the British pound, translates between several languages, does date/time math, and more.
The Multivalent PDF Tools is a suite of tools for manipulating PDF documents. It includes tools for compressing, uncompressing (for hand editing), obtaining metadata, splitting and merging, encrypting and decrypting, validating, imposition (aka n-up), making page images, extracting text, and full-text indexing (with Lucene). The compress tool shrinks the PDF 1.5 Reference from 13.5MB to 8MB in PDF 1.5/Acrobat 6 format and down to 5.1MB in a new proposed "Compact" format.
No-install Unix Tools for Windows is a collection of 18 of the most useful Cygwin tools packaged into a single 1.1MB (floppy sized) EXE file that runs without any installation process. Simply running the executable instantly creates a Unix environment for Windows, without making any persistent changes to the underlying system. It includes bash, less, gzip, grep, find, df, du, ls, cat, cp, mv, ps, rmdir, mkdir, rm, pwd, and tar.
The XNGR XML Browser is an XML browser framework, written in Java, that provides the functionality to associate Markers with directories, files, XML documents, and nodes in an XML document. Services and Actions can be associated to inspect and manage these marked items. Default services include a simple XML Editor and XML Viewer.