DBIx-Class is an SQL to OO mapper with an object API inspired by Class::DBI (with a compatibility layer as a springboard for porting) and a resultset API that allows abstract encapsulation of database operations. It aims to make representing queries in your code as Perl-ish as possible while still providing access to as many of the capabilities of the database as possible, including retrieving related records from multiple tables in a single query.
PPM-Make is a Perl module that automates some of the steps needed to make a ppm (Perl Package Manager) package from a CPAN distribution. It attempts to fill in the ABSTRACT and AUTHOR attributes of Makefile.PL if these are not supplied, and also generates HTML documentation. ppm is used in the ActivePerl distribution. ActivePerl is primarily used on Windows and by corporations on other OSes.
Dist::Zilla builds distributions of code to be uploaded to the CPAN. In this respect, it is like ExtUtils::MakeMaker, Module::Build, or Module::Install. Unlike those tools, however, it is not also a system for installing code that has been downloaded from the CPAN. Since it's only run by authors, and is meant to be run on a repository checkout rather than on published, released code, it can do much more than those tools, and is free to make much more ludicrous demands in terms of prerequisites.
Test::Class provides a simple way of creating classes and objects to test your Perl code in an xUnit style. Built using Test::Builder, it was designed to work with other Test::Builder-based modules. You can easily package your tests as classes/modules rather than *.t scripts. This simplifies reuse, documentation, and distribution, encourages refactoring, and allows tests to be extended by inheritance.
Fedora-Bugzilla is a Perl module that aims to expose a kinder, gentler interface to Fedora/RedHat's Bugzilla implementation, which has a large number of custom methods. In addition to the XML-RPC methods that Bugzilla makes available, there are also some things that can be accessed only via the Web/XML interfaces, such as the flags, attachments, and comments functionality. This package works to expose those as well.