var YSpeed : float;
var YAngle : float;
var MaxY : float;
var MinY : float;
var Direction : Vector3;

function Update () {
YAngle = Mathf.Clamp (YAngle + Time.deltaTime * Mathf.Clamp(Input.GetAxis ("Mouse Y"), -1.5, 1.5) * YSpeed, MinY, MaxY);
Direction = Vector3 ( 0, Mathf.Sin ( Mathf.Deg2Rad * YAngle), Mathf.Cos ( Mathf.Deg2Rad * YAngle));
transform.localRotation = Quaternion.Slerp ( transform.localRotation, Quaternion.LookRotation (Direction), Time.deltaTime * 20);
}