I find this loop code clean and pretty when it comes to executing repetitive animation, something repetitive along the off and on lines for multiple instances on a Timer or a EnterFrame events.
We create a field

private var _counter:int;

and irritate through an array of display objects using it to witch on the next item and switch off the previous one.
In this particular example we switch an array of display objects filers on and off.

(_counter != _items.length - 1) ? _counter++ : _counter = 0;
_items[_counter].filters = _filters;
var previousItem : Number = (_counter != 0 ) ?
_counter - 1 : _items.length - 1;

_items[previousItem].filters = null;

Full example code:

package
{
    import flash.display.Sprite;
    import flash.events.Event;
    import flash.utils.Timer;
    import flash.filters.DropShadowFilter;
    import flash.events.TimerEvent;

/**
* ...
* @author L.gn
*/
    public class Main extends Sprite
    {

         private var _timer:Timer;
         private var _items:Array = [];
         private var _filters:Array = [];
         private var _counter:int = 0;

    public function Main():void
    {

         var i:int;
         for (i = 0; i < 5; i++) {
         var shape:Sprite = new Sprite();
         shape.graphics.beginFill(0xff0000);
         shape.graphics.drawCircle(0, 0, 20);
         shape.y = 200;
         shape.x = i * shape.width + 10;
         shape.graphics.endFill();
         _items.push(shape);
         this.addChild(shape);
         }

         var shadow:DropShadowFilter = new DropShadowFilter();
         _filters.push(shadow);

         _timer = new Timer(1000);
         _timer.addEventListener(TimerEvent.TIMER, animationTickHandler);
         _timer.start();

     }

     private function animationTickHandler(event : TimerEvent) : void {
         //check if the counter reached the length
         // of the array if it did the it should be 0 if not add 1 to it
         (_counter != _items.length - 1) ? _counter++ : _counter = 0;

         //add filters to the item
         _items[_counter].filters = _filters;

         //find the previous item, if the counter not 0
         //then subtract 1 other wise counter should be the lenght of the items array
         var previousItem : Number = (_counter != 0 ) ? _counter - 1 : _items.length - 1;

         //remove filters from item.
         _items[previousItem].filters = null;
     }

  }

}