Simple BlendMode Nav

stage.frameRate=30;
var nav:Sprite = Sprite(addChild(new Sprite()));
nav.x=nav.y=150;

var cover:Sprite;
var coverDest:Number=0;
var spacing:int=4;
var btnNum:int=6;

buildNav();

addEventListener(Event.ENTER_FRAME, onLoop);

function onLoop(evt:Event):void {
	cover.x += (coverDest - cover.x) /4;
}

function buildNav():void {
	for (var i:int = 0; i<btnNum; i++) {
		var b:Sprite=makeBox(50,50);
		b.x = i * (b.width + spacing);
		b.buttonMode=true;
		b.addEventListener(MouseEvent.CLICK, onClick);
	}
	cover=makeBox(54, 60);
	cover.blendMode=BlendMode.INVERT;
}

function onClick(evt:MouseEvent):void {
	coverDest=evt.currentTarget.x;
}

function makeBox(w:Number, h:Number) {
	var b:Sprite = new Sprite();
	with (b.graphics) {
		beginFill(0x000000),drawRect(-w/2,-h/2,w,h);
	}
	nav.addChild(b);
	return b;
}

This is something I do in my intermediate flash classes… the only difference is that we do the graphics in the flash IDE during class time instead of drawing them with ActionScript.