Configuration cfg = new Configuration();
            cfg.AddAssembly("HibernateSandbox");

            ISessionFactory factory = cfg.BuildSessionFactory();           
            ISession session = factory.OpenSession();
            ITransaction transaction = session.BeginTransaction();
           
            User newUser = new User();
            newUser.Id = "k3";
            newUser.UserName = "Topper";

            session.Save(newUser);

            transaction.Commit();
            session.Close();

            session = factory.OpenSession()
            [b]User joeCool = (User)session.Load(typeof(User), "k3");[/b]
            joeCool.UserName = "otherName";
            session.Flush();