first.rb

def get_bread_crumb(request, separator = " » ", breadcrumb = [], so_far = '/')
  url = request.respond_to?(:request_uri) ? request.request_uri : request
  elements = url.split('/')
  
  elements.each_with_index do |element, i|
    is_last = i == elements.size - 1  # whether this is the last item or not
    so_far += element + '/'           # the URL for this element
    breadcrumb <<                     # append this element to the breadcrumb
    case element
      
    when /^\d+$/
      begin
        previous = elements[i - 1]
        record = previous.singularize.camelize.constantize.find(element)
        link_to_unless(last, record.display_name, so_far)
      rescue ActiveRecord::RecordNotFound
        element
      end
      
    else
      link_to_unless(last, element.gsub("_"," ").titleize, so_far)
      
    end
  end
  
  breadcrumb.join(separator)
rescue
  'Not available'
end

second.rb

def get_bread_crumb(request, options = {}, breadcrumb = [], so_far = '/')
  options.reverse_merge!( :not_available  => "Not available",
                          :separator      => " » " )
  url = request.respond_to?(:request_uri) ? request.request_uri : request
  elements = url.split('/')
  
  elements.each_with_index do |element, i|
    is_last = i == elements.size - 1  # whether this is the last item or not
    so_far += element + '/'           # the URL for this element
    breadcrumb <<                     # append this element to the breadcrumb
    case element
      
    when "" then next
      
    when /^\d+$/
      begin
        previous = elements[i - 1]
        record = previous.singularize.camelize.constantize.find(element)
        link_to_unless(last, record.display_name, so_far)
      rescue ActiveRecord::RecordNotFound
        element
      end
      
    else # String
      link_to_unless(last, element.gsub("_"," ").titleize, so_far)
      
    end
  end
  
  breadcrumb.join(options[:separator])
rescue
  options[:not_available]
end