Example code for "Where did that component go?" blog post on AngryAnt.com

ComponentLister.cs

using UnityEngine;
using UnityEditor;
using System.Collections;


public class ComponentLister : EditorWindow
{
	private Hashtable sets = new Hashtable();
	private Vector2 scrollPosition;



	[ MenuItem( "Component/Component lister" ) ]
	public static void Launch()
	{
		EditorWindow window = GetWindow( typeof( ComponentLister ) );
		window.Show();
	}



	public void UpdateList()
	{
		Object[] objects;

		sets.Clear();

		objects = FindObjectsOfType( typeof( Component ) );
		foreach( Component component in objects )
		{
			if( !sets.ContainsKey( component.GetType() ) )
			{
				sets[ component.GetType() ] = new ArrayList();
			}

			( ( ArrayList )sets[ component.GetType() ] ).Add( component.gameObject );
		}
	}



	public void OnGUI()
	{
		GUILayout.BeginHorizontal( GUI.skin.GetStyle( "Box" ) );
			GUILayout.Label( "Components in scene:" );
			GUILayout.FlexibleSpace();

			if( GUILayout.Button( "Refresh" ) )
			{
				UpdateList();
			}
		GUILayout.EndHorizontal();

		scrollPosition = GUILayout.BeginScrollView(scrollPosition);

			foreach( System.Type type in sets.Keys )
			{
				GUILayout.Label( type.Name + ":" );
				foreach( GameObject gameObject in ( ArrayList )sets[ type ] )
				{
					if( GUILayout.Button( gameObject.name ) )
					{
						Selection.activeObject = gameObject;
					}
				}
			}

		GUILayout.EndScrollView();
	}
}