This is a list of the 30 most downloaded Ruby projects (according to RubyForge).

Rank Project Downloads
1

One-Click Ruby Installer

A self-contained installer that includes the Ruby language, dozens of popular extensions, a syntax-highlighting editor and the book "Programming Ruby: The Pragmatic Programmer's Guide". Platforms: Windows NT/2000/XP, (OS X in development).

1,322,138
2

RubyGems

RubyGems is the Ruby standard for publishing and managing third party libraries.

656,227
3

Instant Rails

Instant Rails is a one-stop Rails runtime solution containing Ruby, Rails, Apache, and MySQL, all preconfigured and ready to run. No installer, you simply drop it into the directory of your choice and run it. It does not modify your system environment.

248,676
4

Rails

Rails is a web-application framework for the MVC pattern that includes both a template engine, controller framework, and object-relational mapping package. Everything needed to develop web-apps that can run on CGI, FastCGI, and mod_ruby.

212,899
5

Ruby

Main Ruby language project for providing a mirror of the Ruby releases, tracking bugs, etc.

94,037
6

Instiki

A wiki clone pretty and easy to set up. Runs on Rails and focuses on portability and stability. Supports file uploads, PDF export, RSS, multiple users and password protection. Some use Instiki as a CMS because of it’s ability to export static pages.

72,219
7

RMagick

An interface to the ImageMagick (www.imagemagick.org) and GraphicsMagick (www.graphicsmagick.org) image processing libraries. Supports more than 90 image formats, including GIF, JPEG, PNG. Includes RVG, a 2D drawing API. Comprehensive HTML documentation.

66,665
8

Watir

Watir is a testing tool for automating browser-based tests of web applications. It is a Ruby library that works with Internet Explorer on Windows.

58,004
9

Win32 Utils

A series of packages that provide Ruby interfaces to Win32 systems and services. This project supports the Windows NT family of operating systems *only*.

57,726
10

Nitro

Nitro is an efficient, yet simple engine for developing professional Web Applications using the Ruby language.

51,503
11

ActiveRecord

Implements the ActiveRecord pattern (Fowler, PoEAA) for ORM. It ties database tables and classes together for business objects, like Customer or Subscription, that can find, save, and destroy themselves without resorting to manual SQL.

50,906
12

FreeRIDE

The FreeRIDE project is a pure Ruby Integrated Development Environment.

49,433
13

FLVTool2

FLVTool2 is a manipulation tool for Macromedia Flash Video files (FLV). It can calculate a lot of meta data, insert an onMetaData tag, cut FLV files, add cue points (onCuePoint), show the FLV structure and print meta data information in XML or YAML.

48,753
14

Action Pack

Eases web-request routing, handling, and response as a half-way front, half-way page controller. Implemented with specific emphasis on enabling easy unit/integration testing that doesn't require a browser.

48,323
15

Rake

Rake is a Ruby make-like utility using standard Ruby syntax for the build specification file.

48,087
16

typo

Typo is a lean weblogging engine powered by rails. It supports XMLRPC posting, ping/trackback, comments, textile, markdown, categories, all common exports, fulltext search and so on.

46,193
17

Ruby/DBI

Ruby/DBI develops a database independent interface for accessing databases - similar to Perl's DBI.

44,827
18

SQLite-Ruby

A Ruby interface for the SQLite database engine.

40,968
19

Action Mailer

Simplifies the creation of mail service classes that uses Action View (from Action Pack) to render the body templates.

38,369
20

FXRuby

FXRuby is an extension module for Ruby that provides an interface to the FOX GUI toolkit.

37,509
21

Active Support

Utility classes and extension to the standard library that were required by Rails, but found of general use.

33,196
22

Action Web Service

Simple support for publishing Web Service APIs for Rails applications. Supports SOAP and XML-RPC, as well as generating WSDL for SOAP bindings.

30,486
23

wxRuby

wxRuby is a cross-platform GUI toolkit with a comprehensive widget set and native look and feel. It's based on the mature wxWidgets framework. The wxruby2-preview releases offer the most complete, correct and up-to-date port of the library.

24,201
24

Ruby For Apache - Windows

NOTICE: THIS PROJECT IS DISCONTINUED. PLEASE USE 'INSTANTRAILS' INSTEAD. A self-contained installer that includes mod_fastcgi and mod_ruby for Apache 2.0 and corresponding Ruby extensions for Windows platform.

23,401
25

Mongrel

A small fast HTTP server written in (mostly) Ruby that can be used to host web frameworks directly with HTTP rather than FastCGI or SCGI.

23,237
26

RWD Applications

Ruby scripts that can be used with the RubyWebDialogs GUI interface. These tools and applications are useful for simple tasks.

22,881
27

Ruby/OCI8

Ruby/OCI8 is a ruby interface for Oracle using OCI8 API. It is available with Oracle8, Oracle8i, Oracle9i, Oracle10g and Oracle Instant Client. Use oracle module by yoshidam in RAA for Oracle7.

20,279
28

libxml

libxml bindings for Ruby.

19,663
29

Ruby PDF Tools

Tools written in pure Ruby (no C extensions) for working with PDF documents.

19,340
30

Net::SSH

Net::SSH is to SSH as Net::Telnet is to Telnet and Net::HTTP is to HTTP. Perform non-interactive SSH processing, purely from Ruby!

16,698

View the full list of the top 100 downloads at RubyForge…