object.Drives 

function ShowDriveList()
{
   var fso, s, n, e, x;
   fso = new ActiveXObject("Scripting.FileSystemObject");
   e = new Enumerator(fso.Drives);
   s = "";
   for (; !e.atEnd(); e.moveNext())
   {
      x = e.item();
      s = s + x.DriveLetter;
      s += " - ";
      if (x.DriveType == 3)
         n = x.ShareName;
      else if (x.IsReady)
         n = x.VolumeName;
      else
         n = "[Drive not ready]";
      s +=   n + "<br>";
   }
   return(s);
}

Function ShowDriveList
   Dim fso, d, dc, s, n
   Set fso = CreateObject("Scripting.FileSystemObject")
   Set dc = fso.Drives
   For Each d in dc
      n = ""
      s = s & d.DriveLetter & " - " 
      If d.DriveType = 3 Then
         n = d.ShareName
      ElseIf d.IsReady Then
         n = d.VolumeName
      End If
      s = s & n & "<BR>"
   Next
   ShowDriveList = s
End Function