GameObject size in Inspector

I can't seem to find an easy way to view a GameObject's size in the Inspector..

Am I missing some data somewhere or am I going to have to extend the editor?

If I need to add editor code, I would prefer to have the size data added to the Transform box right under the scale.. but I can't seem to get my editor code to work (it doesn't even show in inspector):

 @CustomEditor (size)
 class size extends EditorWindow     {
     function OnInspectorGUI () {
     
        var bounds : Bounds = GameObject.mesh.bounds;
        EditorGUILayout.Vector3Field ("Size", Vector3(bounds.size.x,bounds.size.y,bounds.size.z));
        if (GUI.changed) {
            var bounds2 : Bounds = GameObject.mesh.bounds;
            EditorGUILayout.Vector3Field ("Size", Vector3(bounds2.size.x,bounds2.size.y,bounds2.size.z));
        }
     }
 }