var banner = new Array();

banner[0]='http://img706.imageshack.us/img706/3866/spikel2copia.jpg';
banner[1]='http://img97.imageshack.us/img97/7708/sinttulo1rhi.png';
banner[2]='http://img820.imageshack.us/img820/525/baanerrspike.jpg';
banner[3]='http://img204.imageshack.us/img204/3048/spikelbaner3.jpg';
banner[4]='http://img580.imageshack.us/img580/7018/spikelforos.png';
banner[5]='http://img337.imageshack.us/img337/9943/bannerspik.png';
banner[6]='http://img375.imageshack.us/img375/9251/spikelcomunidad.png';
banner[7]='https://i.servimg.com/u/f30/14/90/18/07/sin_ta10.png';

document.getElementById('logo').firstChild.src= banner[Math.floor(Math.random()*banner.length)];