Edit in JSFiddle

$(function () {
    var bg_image = $("#image");  
    var x = 0, y = 0;
    bg_image.css('backgroundPosition', '0px' + ' ' + '0px');
    window.setInterval(function() {
        bg_image.css("backgroundPosition", x + 'px' + ' ' + y + 'px');  
        y--;
    }, 80);  
});

<div id="image">
    <span>Key Note / william.neuheisel</span>
</div>

span {
    font-size: 10px;
}
#image {
    width:200px;
    height: 200px;
    background:url(http://farm3.static.flickr.com/2657/3922107796_ccc342077e_m.jpg);
}