images = new Array(1);

images[0] = "<a href = 'http://www.mantality.co.za/stuff/outdoor/firesteel.html'><img src='images/promotional_images/Category-Firesteel.jpg' class='header-image' alt='Firesteel' title='Firesteel' border='0' ></a>";

index = Math.floor(Math.random() * images.length);

document.write(images[index]);