Elvis is a clone of vi/ex, the standard UNIX editor. Elvis supports nearly all of the vi/ex commands, in both visual mode and ex mode. Elvis adds support for multiple files, multiple windows, a variety of display modes including "hex" and "html", on-line help, WYSIWYG printing, and other miscellaneous extensions.
FreeMarker is a template engine that was originally designed so that servlet-based applications could keep graphical design separate from application logic. The templates provide an easy and highly flexible way to generate any kind of text output (HTML, PostScript, TeX, source code, etc.) from a variety of data sources such as Java objects, Jython objects, XML object models, and more.
ICU provides a Unicode implementation, with functions for formatting numbers, dates, times, and currencies (according to locale conventions, transliteration, and parsing text in those formats). It provides flexible patterns for formatting messages, where the pattern determines the order of the variable parts of the messages, and the format for each of those variables. These patterns can be stored in resource files for translation to different languages. Included are more than 100 codepage converters for interaction with non-unicode systems.
Text::Template is a module for doing dynamic content generation in Perl. You can embed any Perl code into a file, and then make a call to the module to `fill in' the blanks in the file. This is good for generating HTML pages and form letters. It was first released in 1995 and is very stable, very fast, and very reliable. It is also integrated with Perl's Safe module in case you don't trust the template author.
XMLDB uses an RDBMS to persist arbitrary XML documents. Due to its storage mechanism, searching for and recalling documents is extremely quick. You can also perform XSL translation on documents with surprising speed. The library can be used in any program to store libxml2 documents. A PHP module is also included, making XMLDB into a complete three-tier Web application development suite.
Enca detects the encoding of text files, on the basis of knowledge of their language. It can also convert them to other encodings, allowing you to recode files without knowing their current encoding. It supports most of Central and East European languages, and a few Unicode variants, independently on language.
DOMC is a lightweight implementation of the Document Object Model (DOM) in ANSI C as specified in the W3C DOM Core Level 1 recommendation. When coupled with the Expat XML Parser Toolkit, DOMC can load, store, build, and directly manipulate XML documents represented as a tree in memory.
The config_cfe Perl module contains functions that ease updating small text files, usually configuration files. It is easy to write small scripts that can do editing in 'batch mode', a necessary thing when updating many hosts at the same time. There is a simple program, update-cfe, that can be used in shell scripts (sometimes update-cfe is enough to update a section in a file).