Outlined new concept for multiple periodically recurring tasks (#3).

app/models/periodic_task_group.rb

@@ -0,0 +1,23 @@
+class PeriodicTaskGroup < ActiveRecord::Base
+  has_many :tasks, :inverse_of => :periodic_task_group, :dependent => :destroy
+
+  PeriodDays = 7
+  
+  def has_next_task?
+    return false if self.tasks.empty?
+    return false if self.tasks.first.due_date.nil?
+    return true
+  end
+
+  def create_next_task
+    template_task = self.tasks.first
+    self.next_task_date ||= template_task.due_date + PeriodDays
+    
+    next_task = template_task.dup
+    next_task.due_date = self.next_task_date    
+    next_task.save
+
+    self.next_task_date += PeriodDays
+    self.save
+  end
+end