build_creation_settings.rb

  def build_creation_settings(params)
    type = self.attributes["creation_setting_type"]
    #create an array with the name of all application models
    models = []
    Dir.glob( RAILS_ROOT + '/app/models/*' ).each do |f| 
      models << File.basename( f ).gsub( /^(.+).rb/, '\1').camelize 
    end 
    #check to make sure that the type is actually a model before passing it
    #through the scarriness of eval()
    if models.include? type
      self.creation_setting = eval(type).new(params)
    else
      raise "We have a run_setting_type that is not any recognized model - perhaps we have hackers on the loose!!!"
    end
  end