arrBanners = [];

arrBanners.push({
				percent: 100,
				image: "http://oystermag.com/wp-content/themes/oyster-3/advertising/med-rec-01/subscribe.gif",
				link: "http://www.magnation.com/Oyster-3021.php"
				});
arrBanners.push({
				percent: 0,
				image: "http://oystermag.com/wp-content/themes/oyster-3/advertising/med-rec-01/Paul_Mitchell_banner.gif",
				link: "http://www.styleicons.com.au/paulmitchell/"
				});


function getRandomBanner() {
  var curr = 0;
  var rand = Math.round(Math.random()*100);
  for (var i=0; i<arrBanners.length; i++) {
    curr += arrBanners[i].percent;
    if (rand <= curr) {
      return '<a href="' + arrBanners[i].link + '" target="_blank"><img src="' + arrBanners[i].image + '" border="0"/></a>';      
    }      
  }
  return '<a href="' + arrBanners[0].link + '" target="_blank"><img src="' + arrBanners[0].image + '" border="0"/></a>';
}

document.write(getRandomBanner());