serve. Serve is a rapid prototyping framework for Rails applications. It is designed to compliment Rails development and enforce a strict separation of concerns between designer and developer. Using Serve with Rails allows the designer to happily work in his own space creating an HTML prototype of the application, while the developer works on the Rails application and copies over HTML from the prototype as needed. This allows the designer to focus on presentation and flow while the developer can focus on the implementation.
10togglejs. A LowPro and Prototype-based library with a collection of behaviors for unobtrusively toggling elements on and off via links, checkboxes, selects, etc.
8uaid. A small library useful to Rack-based Ruby applications for obtaining information about the user agent
6dateinputjs. A LowPro and Prototype-based date input control
6statusjs. Allows you to display a status message when submiting a form or performing other time consuming tasks
6javascript_spec.
5paperclip. Paperclip File Management Plugin
5spec_integration. Rails integration testing support for RSpec, plus useful 'domain' extensions and matchers.
5webrat. Webrat - Ruby Acceptance Testing for Web applications
5popupjs. A prototype/lowpro based Facebook-style windowing solution
5texp. Temporal Expressions for Ruby
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