Jotform have an API, and an official Ruby client, but it's not a gem. Now it is.

Jouba is a tool set for event sourcing: aggregate root, entities and storage

Jouba-SQL is a Storage implementation of Jouba

a library that reads and write ledger format ledger files

Ruby interface to the joyent cloud API

Ruby interface to 'jpegoptim' tool.

株価情報を取得してあれこれするライブラリ

helper methods for generating markup, soon: javascript helpers

Gem is an engine and is configured to integrate with Rails asset pipeline

Asset pipeline integration for https://github.com/geraldb/jquery.table.js

jQuery-UI-formbuilder is a Ruby on Rails FormBuilder DSL powered by jQuery-UI

No more need to download JQuery UI... just include jqueryui/yourtheme and everything just works! Rails 3.1 and up...

JRUBY Tika connector to read text and metadata from files using Apache Tika 1.1. Usage: Jrtika.read(full_file_path)

JRuby Hazelcast 3.7.2 client

Provides callgrind output for the JRuby profiler

A simple rack app wrapper that gathers request metrics using Coda Hale's metrics library

A simple standalone jetty launcher for jruby rack apps

Gem for js-beautify

read more details on http://www.sencha.com/blog/2010/10/21/make-a-javascript-formatter-with-v8-and-jsbeautifier/

Usage: wrap_js_code('<script>alert('wrap me!');</script>') # => '<code><script>alert('wrap me!');</script></code>'