rnd.today=new Date();
rnd.seed=rnd.today.getTime();

function rnd() {
  rnd.seed = (rnd.seed*9301+49297) % 233280;
  return rnd.seed/(233280.0);
};

function rand(number) {
  return Math.ceil(rnd()*number);
};

var number=rand(8)-1
var ads = new Array(8);
//ads[0]=['someurl','someimage'];
ads[0]=['http://www.startrek.com/startrek/view/store/index.html','commerce_120x600.gif'];
ads[1]=['http://www.startrek.com/startrek/view/store/downloads/index.html','downloads_120x600.gif'];
ads[2]=['http://www.startrek.com/startrek/view/library/episodes/index.html','episode-guide_120x600.gif'];
ads[3]=['http://www.startrek.com/startrek/view/news/index.html','news_120x600.gif'];
ads[4]=['http://reg.startrek.com/registration/startrek/reg.jsp','newsletter-120x600.jpg'];
ads[5]=['http://www.startrek.com/startrek/view/community/reviews/index.html','rate-and-review_120x600.jpg'];
ads[6]=['http://reg.startrek.com/registration/startrek/reg.jsp','registration_120x600.gif'];
ads[7]=['http://www.startrek.com/startrek/view/store/index.html','store_120x600.jpg'];

//document.write('<div align=center><a href="'+ads[number][0]+'"><img src="http://www.startrek.com/html/ads/120x600/'+ads[number][1]+'" alt="click here" border="0"></a></div>');

ord=Math.random()*10000000000000000;
document.write('<div align=center><script language="JavaScript" src="http://ad.doubleclick.net/adj/skyscrapers.startrek.com/;dcopt=ist;sz=120x600;ord=' + ord + '?" type="text/javascript"><\/script></div>');