namespace Server.Impl
{
    class Program
    {
        static void Main(string[] args)
        {
            // Step 1 Create a URI to serve as the base address.
            var baseAddress = new Uri("http://localhost:8000/Server.Impl/");

            // Step 2 Create a ServiceHost instance
            var host = new MyServiceHost("Initialization data should be here", typeof(Service), baseAddress);

            try
            {
                // Step 3 Add a service endpoint.
                host.AddServiceEndpoint(typeof(IService), new WSHttpBinding(), "http://localhost:8000/Server.Impl/service/wshttpbinding");

                // Step 4 Enable metadata exchange.
                var smb = new ServiceMetadataBehavior {HttpGetEnabled = true};
                host.Description.Behaviors.Add(smb);

                // Step 5 Start the service.
                host.Open();
                Console.WriteLine("The service is ready.");
                Console.WriteLine("Press <ENTER> to terminate service.");
                Console.WriteLine();
                Console.ReadLine();

                // Close the ServiceHostBase to shutdown the service.
                host.Close();
            }
            catch (CommunicationException ce)
            {
                Console.WriteLine("An exception occurred: {0}", ce.Message);
                host.Abort();
            }
        }
    }

    public class MyServiceHost : ServiceHost
    {
        public object Data { get; private set; }

        public MyServiceHost(object data, Type serviceType, params Uri[] baseAddresses)
            :base(serviceType, baseAddresses)
        {
            Data = data;
        }
    }
}

var appData = ((MyServiceHost)OperationContext.Current.Host).Data;

class InstanceProvider : IInstanceProvider, IServiceBehavior
{
    private readonly object _instanceData;

    public InstanceProvider(object instanceData)
    {
        _instanceData = instanceData;
    }

    // Реализация обоих интерфейсов опущена
}

object instanceData = new object();
var host = new ServiceHost(typeof (Service));
host.Description.Behaviors.Add(new InstanceProvider(instanceData));

IXX>var appData = ((MyServiceHost)OperationContext.Current.Host).Data;
IXX>