"Hover" object up and down

A really quick and dirty way to achieve this would be to just move the objects y axis along a sine curve. I.e.:

         var Step : float; //A variable we increment
         var Offset : float; //How far to offset the object upwards
         
         function Start () {
         //Store where we were placed in the editor
         var InitialPosition = transform.position;
         //Create an offset based on our height
         Offset = transform.position.y + transform.localScale.y;
         }
         
         function FixedUpdate () {
         
         Step +=0.01;
           //Make sure Steps value never gets too out of hand 
           if(Step > 999999){Step = 1;}
 
           //Float up and down along the y axis, 
           transform.position.y = Mathf.Sin(Step)+Offset;
         }