How do I reference another GameObject's transform?

I have an orbit script that makes an object orbit the origin. What I want is for it to be able to use any other GameObject instead of the origin.

uJS

var originTransform : Transform;

function Update() {
   var something = originTransform.position * something...
}

C#

public class Orbit : MonoBehaviour {
    public Transform originTransform;

    void Update() {
       Vector3 something = originTransform.position * something...
    }
}

This is a very common and basic topic. Take a look at http://docs.unity3d.com/Documentation/ScriptReference/index.Accessing_Other_Game_Objects.html