function ShowBanners ()
{
    var left = $('SubNav').getDimensions();

    total_height_available = left.height-250;

    var f = $$('div#banners .banner');

    $num_banners_shown=0;
	for(var i=0; i<f.length; i++){

        
        element = $(f[i].id).getDimensions();
        
        if (element.height<total_height_available)
        {
            Element.show(f[i].id);
            total_height_available=total_height_available-element.height;
            $num_banners_shown++;
        }
        else if ($num_banners_shown==0)
        {
            // Show at least one banner
            Element.show(f[1].id);
            $num_banners_shown++;
        }

  	}


}