Is there a way to have an object gradually move to one spot, move back, and then stop?

Short version: Is there a way to have an object gradually move to one spot, move back, and then stop?

Long version: I'm trying to make an enemy for a game that moves along the ground and then hops up every two seconds. I've tried to use the Mathf.PingPong function, but I could not find a way to stop it once it gets going. Further, if I put the command in the Start() function, the object teleports to the destinations instead of gradually moving from one spot to the other.

It would be great if there was a Transform command that gradually moves an object to a designated spot, but my searches here and on the web have not turned up anything. If I had that, I could use "while" and "yield WaitForSeconds" to accomplish my AI movement. But the best I can do is have the objects teleport to a certain spot or have an object continuously move up and down.

Any ideas?

Here is my code for those who are curious:

 #pragma strict 
 
 //Stores the position the enemy spawns at 
 var initPos : Vector3; 
 var hopDirection : Vector2; 
 var hopSpeed : float; 
 
 function Start () {  
     initPos = transform.position;     
 } 
 
 function Update() { 
     transform.Translate(Time.deltaTime * -5, 0, 0); 
 } 
 
 function TumbleHop() {  
     transform.position.y = initPos.y + Mathf.PingPong(Time.time * hopSpeed, hopDirection.y);     
     transform.position.x = initPos.x + Mathf.PingPong(Time.time * hopSpeed, hopDirection.x); 
 }