<!-- Principio
var how_many_ads = 10;
var now = new Date()
var sec = now.getSeconds()
var ad = sec % how_many_ads;
ad +=1;

imagenurl="images/fotos/foto_Pesa" + ad + ".jpg";
//alert(imagenurl);
width="354";
height="280";

document.write('<img class="fotocol" align="middle" src=\"' + imagenurl + '\" width=')
document.write(width + ' height=' + height + ' ');
document.write('border=0  class=mini hspace=5>');
// Fin -->