public class Global
{
	//instance variables
 
	static List<Global> CLASSES = new List<Global>();
	public static Global this[int n]
	{
		get { return CLASSES[n]; }
	}
	public Global()
	{
		CLASSES.Add(this);
	}
}

using System;
using System.Collections.Generic;
 
public class Global
{
    private static readonly List<Global> CLASSES = new List<Global>();
    public static int Count
    { get { return CLASSES.Count; } }
    public static Global Get(int index)
    { return CLASSES[index]; }
 
    public int value;
 
    public Global()
    { CLASSES.Add(this); }
}
 
public static class Test
{
    static void Main()
    {
        new Global();
        Global.Get(0).value = 1;
        Console.WriteLine(Global.Get(0).value);
        Console.ReadKey();
    }
}