Before, After and Around methods, either with blox or methods, à la ActiveSupport

Define configuration values with defaults and lazy evaluation on a per class or per instance level

Functional Access to Methods - Memoization - Extending Array, Hash, File, Enumerable with convenience methods, conceptual changes have been moved into lab42_more

A Hash with Business Logic (call it intelligent).

A Nested Hash with dotted access à la I18n in Rails

Specify command line arguments with Ruby Syntax

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.

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.

Ruby Mixers is collection mixin modules for the Ruby programming language. Mixers is a spin-off of Ruby Facets. When Ruby Facets scaled back to extensions only project, it's mixin modules were gathered to create this new project.

Never use XSLT again...

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.

Radix is a very easy to use Ruby library for converting numbers to and from any base. It supports both Integer, Float and Rational numbers, as well as representational string-notations that need not be in ASCII order. (String patches removed to work with Ruby 2.1 See https://github.com/rubyworks...

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.