<?php
function convertCurrency($amount, $from, $to) {
     $url = 'http://finance.google.com/finance/converter?a=' . $amount . '&from=' . $from . '&to=' . $to;
     $data = file_get_contents($url);
         preg_match_all("/<span class=bld>(.*)<\/span>/", $data, $converted);
         $final = preg_replace("/[^0-9.]/", "", $converted[1][0]);
        return round($final, 3);
   }

   echo convertCurrency(1, 'EUR', 'PLN');  // output: 1.195

   echo convertCurrency(1, 'USD', 'PLN');  // output: 1.195

/* I got errors until i've changed this line:
   $final = preg_replace("/[^0-9.]/", "", $converted[1]); to:
   $final = preg_replace("/[^0-9.]/", "", $converted[1][0]);
   .. maybe it works for your code too
*/
?>