Window Open in XML format

[week]

I have an ASP page that displays the XML string output that's generated by javascript call. The problem is that it is hard to read what's being displayed. We need it to be displayed as how it displays when one clicks on an .xml file with all same level tags lined up nicely...much easier to read the XML string that way. This will be accomplished through window.open function. But not sure how to display the string in a nice formated way....

Hope I am making it clear on what I need to accomplish here...

Thanks for your help!