gistfile1.rb

        # New utility method to return ancestors and siblings and children
        def ancestors_siblings_children
          query = "#{scope_condition} AND (#{self[left_col_name]} BETWEEN #{left_col_name} AND #{right_col_name})  OR  #{parent_col_name} = #{self.id} OR id = #{self.id}"

          unless self[parent_col_name].nil?
            query << " OR  #{parent_col_name} = #{self[parent_col_name]}"
          end
          base_set_class.find(:all, :conditions => query, :order => left_col_name )

        end