The Library class encapsulates the essential nature of a Ruby library --a location on disk from which scripts can be required.

Lime is a pure Ruby variation of Cucumber's Gherkin BDD test system that runs on top of RubyTest, a Universal Test Harness for Ruby.

Loadable modifieds Ruby's load/require system to handle "load wedges", which work much like routes in web frameworks, but in this case determine which files get loaded.

LOCat is a customizable Lines-Of-Code analysis tool. LOC might not be the most useful metric in the universe, but it still provides useful information and can be a lot of fun.

XDG provides an interface for using XDG directory standard.

Malt provides a factory framework for rendering a variety of template and markup document formats.

Mast is a command line tool for generating manifests and digests. Mast makes it easy to compare a manifest to a current directory structure, and to update the manifest with a simple command by storing the command options it the manifest file itself.

MicroTest is a very small Test::Unit/MiniTest compatbile test framework that runs on top of RubyTest, a Universal Test Harness for Ruby.

Neapolitan is a meta-templating engine. Like a candy store it allows you to pick and choose from a variety of rendering formats in the construction of a single document. Selections include eruby, textile, markdown and many others.

NoBacksies is a callback layer built on top of Ruby's built-in callback methods. It makes it possible to add new callbacks very easily, without having to fuss with more nuanced issues of defining and redefining callback methods.

OpenDSL is the ultimate DSL system. It marries Ruby's metaprogramming chops with it's versitle mixin system to create a remarkably simple but incredibly powerful DSL framework.

PIC is a pattern matching library, like regular expressions, based on Cobol edited pictures. It's advantage over regular expressions is it more concise syntax which geared specifically toward validation of user input.

Provides a complete double-dispatch type conversion system, method overloadability and psuedo-classes.

RagTag is a Ruby variation on Zope Page Templates and it's TAL specification. It primarily differs from ZPT in that it is specifically geared for use with Ruby.

RAML is a Ruby-syntax-based data language.

R.C. is a multi-tenant runtime configuration system for Ruby projects. It can be used to configure almost any Ruby tool or library regardless of whether that tool or library has dedicated support for RC or not.

RDoc-Shomen is an RDoc generator plugin that can be used to generate Shomen documentation. This is an alternative to the shomen command line tool which use the `.rdoc` cache to generate a shomen document. In contrast the rdoc-shomen generator operates as a traditional rdoc plugin.

Ever thought perhaps that all the effect in creating a good README, while great for your end-userss, did't every do you a hill of beans worth of good when it came to constructing your project's metadata. Well, hang on to your nerd glasses! Here comes a gem that does just that!

Real makes true reflection possible for Ruby objects. This can be important to metaprogrammers who need to ensure they have the true information.

A Unit system, based on Rich Kilmer's original time.rb work, which provides english-esque methods for working with common units, such as days and bytes and multiplers like kilo, or mega. It does so by reducing basic measures to a lower common denominator, such as seconds for time measures and bits for byte measures.