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="Weddings by the Sea"; 
url="http://www.weddingsbythesea.com";
alt="Weddings by the Sea";
banner="http://www.coastsidelive.com/banners/weddingsbythesea-banner.jpg";
width="450";
height="50";
}

if (ad==2) {
txt="Get found! Sponsor an ad here."; 
url="http://www.coastsidelive.com/sponsor.html";
alt="Get your site found! Sponsor an ad here.";
banner="http://www.coastsidelive.com/banners/sponsor-ad-banner-2.gif";
width="468";
height="60";
}

if (ad==3) {
txt="Half Moon Bay Kayak"; 
url="http://www.hmbkayak.com";
alt="HMB Kayak, Half Moon Bay";
banner="http://www.coastsidelive.com/banners/hmbkayak.gif";
width="470";
height="70";
}

document.write('<center>');
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>');
document.write('</center>');