Sockets for Unity3D coroutine.
Cosocket sock = new Cosocket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
yield return StartCoroutine(sock.Connect(new IPEndPoint(IPAddress.Parse("127.0.0.1"), 8999)));
yield return StartCoroutine(sock.Send(new ASCIIEncoding().GetBytes("Hello, world")));