messager.cs

using System;
using System.Collections.Generic;
using System.Linq;

public class Test
{
    public static void Main()
    {
        Message m1 = new Message { reciver = "one", fun = () => { Console.WriteLine("Say this"); } };
        Messager.Send(m1);
        var ms = Messager.Get("one");
        foreach (var m in ms)
        {
            m.fun();
        }
    }
}

public class Message
{
    public String reciver;
    public Action fun;
}

public static class Messager
{
    private static object locker = new Object();
    private static List<Message> Queue = new List<Message>();

    public static List<Message> Get(String name)
    {
        List<Message> retval = new List<Message>();
        lock (locker)
        {
            foreach (var m in Queue)
            {
                if (m.reciver == name)
                {
                    retval.Add(m);
                }
            }
            Queue = Queue.Except(retval).ToList();
        }
        return retval;
    }

    public static void Send(Message m)
    {
        lock (locker)
        {
            Queue.Add(m);
        }
    }
}