function banner() {
};

banner = new banner();
number = 0;

// bannerArray
banner[number++] = "<a href='http://tracker.tradedoubler.com/click?p=1393&a=925829&g=86850'><img src='http://impgb.tradedoubler.com/imp/img/86850/925829' border=0></a>"
banner[number++] = "<a href='http://tracker.tradedoubler.com/click?p=1393&a=925829&g=86911'><img src='http://impgb.tradedoubler.com/imp/img/86911/925829' border=0></a>"
banner[number++] = "<a href='http://tracker.tradedoubler.com/click?p=1393&a=925829&g=86866'><img src='http://impgb.tradedoubler.com/imp/img/86866/925829' border=0></a>"
banner[number++] = "<a href='http://tracker.tradedoubler.com/click?p=1393&a=925829&g=86828'><img src='http://impgb.tradedoubler.com/imp/img/86828/925829' border=0></a>"
// keep adding items here...

increment = Math.floor(Math.random() * number);

document.write(banner[increment])