The Loop in Archive.php

Hello guys,

I have this loop in Archive.php :

<?php
	query_posts($query_string.'&posts_per_page=8');
	if (have_posts()) : ?>
	<?php while (have_posts()) : the_post(); ?>

	// code, stuff, more code

	<?php endwhile; ?>

	<?php else : ?>

	// code, stuff, more code

	<?php endif; ?>

Inside that loop, I’m assigning to every div containing a post it’s post’s ID.

<div id="<?php the_ID(); ?>">
	//title, content, tags
	</div>

Later, I need, again, the same pack of IDs outside the loop.

My question is : how can I call TWICE for the same loop ?
Or :
Can I store anywhere the id’s in the first loop, then echo them anywhere else, without needing a second loop ?

How would you do that ?

Many thanks.