Something

            IPEndPoint bind = new IPEndPoint(IPAddress.Any, Settings.Default.ListenPort);
            IPEndPoint conn = new IPEndPoint(IPAddress.Parse("127.0.0.1"), Settings.Default.ListenPort);

            MessageFormatter formatter = new MessageFormatter();

            AsyncSocket receiver = new AsyncSocket(formatter, NetworkProtocol.TCP);

            receiver.ConnectionAccepted += (s, e) => { 
                Console.WriteLine("Connection Accepted");

                //set to use appropriate message formatter
                e.Socket.Formatter = formatter;

                e.Socket.MessageReceived += (s2, e2) => {
                    Console.WriteLine("Message Received!");
                };

                e.Socket.ReceiveAsync(() => { Console.WriteLine("Receive Complete"); });
            };

            receiver.Bind(bind);
            receiver.Listen();

            AsyncSocket sender = new AsyncSocket(formatter, NetworkProtocol.TCP);

            sender.Connect(conn, () => { 
                Console.WriteLine("Connect success: {0}", sender.Connected);

                if (sender.Connected) 
                    sender.SendAsync(new Piece(10, 40, new byte[20]));
            });