Хм , вот что нашел : http://codeguru.ru/web/javascript/samples/%D0%B0%D0%BD%D0%B8%D0%BC%D0%B0%D1%86%D0%B8%D1%8F/%D0%B4%D0%B2%D0%B8%D0%B6%D1%83%D1%89%D0%B8%D0%B5%D 1%81%D1%8F-%D0%BE%D0%B1%D1%8A%D0%B5%D0%BA%D1%82%D1%8B/%D0%BF%D0%B0%D0%B4%D0%B0%D1%8E%D1%89%D0%B8%D0%B9-%D1%81%D0%BD%D0%B5%D0%B3.html