var how_many_ads = 3

var now = new Date()
var sec = now.getSeconds()
var ad = sec % how_many_ads; ad +=1;

if (ad==1)
{
txt="";
url="http://benartstil.biz/sitemap.php" ;
alt="Вашата реклама може да седи тук";
banner="images/banners/your_ad.jpg";
width="468";
height="60";
}

if (ad==2)
{
txt="";
url="http://skyconsult.eu" ;
alt="Счетоводство и консултации - http://skyconsult.eu";
banner="images/banners/sky_468x60.png";
width="468";
height="60";
}

if (ad==3)
{
txt="";
url="http://bgcenter.net" ;
alt="Вашият интернет портал - http://bgcenter.net";
banner="images/banners/bg_center_468.png";
width="468";
height="60";
}
document.write('<a href=\"' + url + '\" target=\"_blank\">'); document.write('<img src=\"' + banner + '\" width=')
document.write(width + ' height=' + height + ' ');
document.write('alt=\"' + alt + '\" border=0><br>');
document.write('<small>' + txt + '</small></a>');