$(window).load(function() {
    $('div.images').find('a').hover(function(){
        // on hovering out, fade the element out
        var fade = $('> img.off', this);
        if (fade.is(':animated')) {
          fade.stop().fadeTo(600, 0);
        } else {
          // fade away slowly
          fade.fadeOut(600);
        }    
    },
    function(){
        // on hovering over, find the element we want to fade *up*
        var fade = $('> img.off', this);
        
        // if the element is currently being animated (to a fadeOut)...
        if (fade.is(':animated')) {
          // ...take it's current opacity back up to 1
          fade.stop().fadeTo(900, 1);
        } else {
          // fade in quickly
          fade.fadeIn(900);
        }
    }
)
});