[monolithed]

как вариант:

<script type="text/javascript">
(function(i) {
      window.setInterval(
          function() {
              var element = document.getElementById('img');
                  images = ['http://png-2.findicons.com/files/icons/1982/social_me/48/google.png',
                            'http://png-5.findicons.com/files/icons/1982/social_me/48/twitter.png',
                            'http://png-4.findicons.com/files/icons/1982/social_me/48/facebook.png'],
              j = images.length;
              ++i < j ? element.src = images[i] : i = -1;
    }, 1500);
}(-1));
</script>

<img src="http://png-4.findicons.com/files/icons/1982/social_me/48/facebook.png" alt="" id="img" />