Rotate Character with movement

Right, I have a simple movement script. I haven't picked up unity in a while and for some reason it seems i have forgotten some of the basics. I want my character to face the direction he is moving. Here is the script i have for movement at the moment.

 var speed : float = 6.0;
 
 var jumpSpeed : float = 8.0;
 
 var gravity : float = 20.0;
 
 private var moveDirection : Vector3 = Vector3.zero;
 
 function Update() {
     var controller : CharacterController = GetComponent(CharacterController);
     
     if (controller.isGrounded) {
         // We are grounded, so recalculate
         // move direction directly from axes
         moveDirection = Vector3(Input.GetAxis("Horizontal"), 0,
                                 Input.GetAxis("Vertical"));
         moveDirection = transform.TransformDirection(moveDirection);
         moveDirection *= speed;
         
         if (Input.GetButton ("Jump")) {
             moveDirection.y = jumpSpeed;
         }
     }
 
     // Apply gravity
     moveDirection.y -= gravity * Time.deltaTime;
     
     // Move the controller
     controller.Move(moveDirection * Time.deltaTime);
 }