Well, responseBody is an array of unsigned bytes and JScript doesn't
support that datatype so there is not much you can do with that property
in JScript, besides passing it on to a method taking that kind of array
as a parameter, for instance
  Response.BinaryWrite

Here is an example reading a GIF image

<%@ Language="JScript" %>
<%
var httpRequest = Server.CreateObject("Msxml2.ServerXMLHTTP.4.0");
httpRequest.open("GET", "http://localhost/javascript/kiboInside.gif",
false);
httpRequest.send();
Response.ContentType = 'image/gif';
Response.BinaryWrite(httpRequest.responseBody);
%>