HTML::Mason is a full-featured web site development and delivery system. Mason allows web pages and sites to be constructed from shared, reusable building blocks called components. Components contain a mix of Perl and HTML, and can call each other and pass values back and forth like subroutines. Components increase modularity and eliminate repetitive work. HTML::Mason is most powerful when used in conjunction with mod_perl, but can be used in standalone applications as well.
libintl-perl is a library that supports message translation for Perl, written in pure Perl (version 5.004 or better). A faster C version is also built and installed if the system fulfills all requirements. Its interface is a superset of the gettext family of functions in C, and it uses the same file formats as GNU gettext, making it possible to use all tools available for gettext itself and to seamlessly integrate internationalized Perl code into mixed-language projects.
Xapian is a search engine library, scalable to collections containing hundreds of millions of documents. It's written in C++ with bindings for Perl, Python, PHP, Java, Tcl, C#, Ruby, and Lua. It is a highly adaptable toolkit that allows developers to easily add advanced indexing and search facilities to their own applications. It supports the Probabilistic Information Retrieval model and also a rich set of boolean query operators. Omega is a Web search application built upon the Xapian library. It can index a Web server's document tree (including HTML, PDF, OpenOffice, MS Word/Excel/Powerpoint/Works, WordPerfect, RTF, PS, etc.), or data exported from arbitrary sources (e.g. SQL databases).
Berkeley DB XML is a native XML database engine for use within your product. Made available as a C++ library with language bindings for Java, Perl, Python, PHP, and Tcl, it integrates directly into your application (it is not a standalone database server). It provides XQuery access into a database of document containers. XML documents are stored and indexed in their native format using Berkeley DB as the transactional database engine.
Gtk2::Ex::DBI is a Perl module that is used in conjunction with Gtk2::Perl and Gtk2::GladeXML to give data-aware "form" functionality. The programmer creates a database form with Glade2, and then creates a Gtk2::Ex::DBI object, which then "binds" a DBI data source to the form, managing querying, navigating records, applying updates to the database, and error handling.