i don't think ones based on document.createElement('script') will work since they will all attach to the dom instantly and i will be maxed out when the script loads...
you could use document.write() instead of document.createElement('script') since that will pause between each potential drive letter, ensuring i is set on the CD drive when the script is parsed.
this should also work to get the base path, from which you can determine the drive letter quite easily:
return "file://" +
String(y.fileName || y.file || y.stack || y + '')
// example usage: alert( __filename() );
BROWSER STATS [% share]
(2013/10/31) IE7:0.5, IE8:8.6, IE9:5.3, IE10:12.3, FF:17.7, CH:41.8, SF:8.1, MOBILE:20.4