         _tickables.remove(tickable);
     }
 
+    /** Everyone who wants to hear about our ticks. */
     protected var _tickables :Array = [];
 
     /** A timer that will fire every "frame". */
     protected var _t :Timer = new Timer(1);
+    
+    /** What time our ticker started running - tickStamps will be relative to this time. */
+    protected var _start :Number;
 }
 }
    public function start () :void
    {
        _t.addEventListener(TimerEvent.TIMER, handleTimer);
        _t.start();
    }



    public function handleTimer (event :TimerEvent) :void
    {
        tick(int(new Date().time - _start));
    }

    protected function tick (tickStamp :int) :void
