//ITS THE RIVERA ERA
//THE FIRST URBAN PUERTO RICAN DEVELOPER

//REPLACE 'instance_name_here' WITH YOUR
//MC OBJECT INSTANCE NAME

import flash.events.Event;
stage.addEventListener(Event.ENTER_FRAME, mMotion);
function mMotion(evt:Event):void
{
	instance_name_here.x = stage.stageWidth / 2;
	instance_name_here.y = stage.stageHeight / 2;
	
	instance_name_here.x +=  Math.floor(Math.random() * 100);
	instance_name_here.y -=  Math.ceil(Math.random() * 100);

	if (instance_name_here.x > stage.stageWidth)
	{
		instance_name_here.x = stage.stageWidth / 2;

		if (instance_name_here.y > stage.stageHeight)
		{
			instance_name_here.y = stage.stageHeight / 2;
		}
	}
}

Produces a 'quake' effect on an instance of a MC. (It's The Rivera Era)

Earthquake Effect (RIVERA ERA)

ActionScript 3