C#

ManagementObjectSearcher searcher = new ManagementObjectSearcher("root\\CIMV2", "SELECT * FROM Win32_ComputerSystem");
    foreach (ManagementObject queryObj in searcher.Get())
        {
           string LOU = (queryObj["UserName"].ToString());// returns domain\username - I found this to be the quickest solution
           WindowsIdentity wi = new WindowsIdentity(LOU);// ref http://msdn.microsoft.com/en-us/library/ms998351.aspx#paght000023_impersonatingbyusingwindowsidentity
// fails here with security exception - should I be passing a token instead?
           WindowsImpersonationContext ctx = null;
           ctx = wi.Impersonate();
           WindowsPrincipal wp = new WindowsPrincipal(wi);

           string LOU1 = wi.Name;
           string AuthType = wi.AuthenticationType;
           string Authd = wi.IsAuthenticated.ToString();
           string isGuest = wi.IsGuest.ToString();
           string SidNo = wi.Owner.ToString();
           string SidPlain = wi.Owner.Translate(typeof(System.Security.Principal.NTAccount)).ToString();
           string Token = wi.Token.ToString();

           Console.WriteLine(LOU1);
           Console.WriteLine(AuthType);
           Console.WriteLine(Authd);
           Console.WriteLine(isGuest);
           Console.WriteLine(SidNo);
           Console.WriteLine(SidPlain);
           Console.WriteLine(Token);

           foreach (System.Security.Principal.IdentityReference group in wi.Groups)
           {
               Console.WriteLine(group.Translate(typeof(System.Security.Principal.NTAccount)));
           }