SchemaView Plus is a GUI for creating, retrieving, drawing, and printing database schema. It uses Perl, Tk, DBI, and XML packages. Schema can be retrieved using DBIx::SystemCatalog, and it uses XML for storing and retrieving data in text files. You can write any filters to modify these XML files to add new functionality based on your projects (e.g. dropping off some relationships).
EFEU is suitable for handling data cubes, which are especially useful for building data warehouses. It consists of a building system including mkmf (a xmkmf like Makefile generator), esh (a powerful C/C++ interpreter), efeudoc (a document generator with different output formats (LaTeX, HTML, roff, etc.)). EFEU has a huge set of C library core features, including robust memory allocation tools, functions to concatenate and copy strings with memory allocation, buffers for dynamically-growing strings and fields, data structures with reference counters and garbage collection, and file tools that allow you to specify pipes wherever a filename is expected and support automatic implementation of (de)compression filters (gzip) depending on filename extensions. It also includes a high-level interface to files, strings, and anything else you can read from or write to.
QaMoose is an English/Arabic user-defined dictionary mechanism that is meant to be used by translators and technical writers in order to establish and retain consistent content (the content is envisioned to come from Arabeyes' Wordlist project). Its two modes include a public DICT Web client alongside a means to suggest and correct terms locally. All code is UTF-8 friendly. There is also an 'admin' page which allows you to apply for a term inspector/approver position.
WebTools is "system" of multiple modules and libraries. Along with template engine capabilities, it features session management, global variables support, cookies support, and various database interfaces. It also features a pure Perl mail client, categories management, form checking, and libraries such as a CGI-based downloading library, HTML parsers, and a library that makes PHP functions available to Perl for ease of development.