function format_price( price )
{
  var i, price_str = price.toFixed(2);
  for (i = price_str.indexOf("."); i > 3; i -= 3)
  {
    price_str = price_str.substr(0, i-3) + "," + price_str.substr(i-3);
  }
  return "$" + price_str;

} // format_price()


function createXMLHttpRequest()
{
  var httpRequest;

  if (window.XMLHttpRequest)
  { // Mozilla, Safari, ...
    httpRequest = new XMLHttpRequest();
    if (httpRequest.overrideMimeType)
    {
      httpRequest.overrideMimeType("text/xml");
    }
  }
  else if (window.ActiveXObject)
  { // IE
    try
    {
      httpRequest = new ActiveXObject("Msxml2.XMLHTTP");
    } catch (e)
    {
      try
      {
        httpRequest = new ActiveXObject("Microsoft.XMLHTTP");
      } catch (e) {}
    }
  }

  return httpRequest;

} // createXMLHttpRequest()