function popItUp(u,w,h)
{
	var l=(screen.availWidth  - w) / 2, t=(screen.availHeight - h) / 2,op='toolbar=no,location=no,directories=no,status=no,scrollbars=yes,resizable=yes,copyhistory=no,width='+w+',height='+h+',left='+l+',top='+t
	window.open(u, '_blank', op)
}
function showCertificate() { popItUp('hide-my-url.php?id=certificates_url',500,350); }
function showSpecialOffer() { popItUp('hide-my-url.php?id=special_offer_url',620,620); }