This works: (try it here: http://is.gd/excbc)
<!-- jQuery is required -->
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>
<!-- the images -->
<div class="showmetoo" style="background: url(jimhance-vader_inset.jpg)">
<br/><br/><br/><br/><br/><br/><br/><br/><br/><br/><br/><br/><br/><br/><br/><br/><br/><br/><br/><br/><br/><br/></div>
<img class="showall" src="octopus3.jpg" alt="a picture"><br/>
<img class="showall" src="moorea.jpg" alt="a picture"><br/>
<!-- hidden by default -->
<style>
img.showall { visibility: hidden }
div.showmetoo { visibility: hidden }
</style>
<!-- the script -->
<script type="text/javascript">
var remaining = $('.showall').length;
function showthem(){
remaining--;
if(!remaining){
$('.showall').css('visibility', 'visible');
$('.showmetoo').css('visibility', 'visible');
}
}
// bind the callback to the load event of the pictures.
$('.showall').bind('load',showthem);
// force the pictures to show (just in case)
setTimeout(showthem, 1000); //just in case load event fires before callback is set.
</script>