Edit in JSFiddle

var images = [];
for(var x=0; x < 500; x++){
    var im = new Image();
    im.src = "http://sandropaganotti.com/wp-content/goodies/misc/smarties.jpg";
    im.onload = function(ev){
        var body = document.querySelector('body');
        body.innerHTML = body.innerHTML + "<img width='25' src='"+ev.target.src+"'>";
    }
}