Read more on Category Description

Hi everyone
So I am working on a wordpress site, and I am working with displayed category descriptions of the posts. So when you click on a category in my menu, you come to page with the overview of posts and a category description.

What I really want to do is to just display some of the category description, with a “Read more/hide” button, that shows the rest of the category description using a nice javascript slide effect or something..

Does anyone know how to help me with this?

This is the code from my archive.php that displays the category description (in the bottom)

<?php get_header(); ?>
    <h3 class="top_title">
        <?php if (is_category()) { ?>
              <?php single_cat_title(); ?>
       <?php } elseif( is_tag() ) { ?>
              <?php single_tag_title(); ?>
        <?php } elseif (is_day()) { ?>
              <?php the_time('F jS, Y'); ?>
        <?php } elseif (is_month()) { ?>
              <?php the_time('F, Y'); ?>
        <?php } elseif (is_year()) { ?>
              <?php the_time('Y'); ?>
        <?php } elseif (is_author()) { ?>

              Author Archive
        <?php } elseif (isset($_GET['paged']) && !empty($_GET['paged'])) { ?>
              Blog Archives
        <?php } ?>
    </h3>

    <div id="content_inside">
    <?php
    global $wp_query;
    $args = array_merge( $wp_query->query, array( 'posts_per_page' => 9 ) );
    query_posts( $args );
    $x = 0;
    while (have_posts()) : the_post(); ?>
        <?php if($x == 2 || $x == 5 || $x == 8 || $x == 11 || $x == 14 || $x == 17 || $x == 20 || $x == 23 || $x == 26 || $x == 29 || $x == 32 || $x == 35 || $x == 38 || $x == 41 || $x == 44) { ?>
            <div class="home_post_box home_post_box_last">
        <?php } else { ?>
            <div class="home_post_box">
        <?php } ?>
            <a href="<?php the_permalink(); ?>" class="home_post_text_back"></a>
            <a href="<?php the_permalink(); ?>"><?php the_post_thumbnail('home-image'); ?></a>

            <a href="<?php the_permalink(); ?>" class="home_post_text">
                <h3><?php the_title(); ?></h3>
            </a><!--//home_post_text-->

        </div><!--//home_post_box-->
        <?php if($x == 2 || $x == 5 || $x == 8 || $x == 11 || $x == 14 || $x == 17 || $x == 20 || $x == 23 || $x == 26 || $x == 29 || $x == 32 || $x == 35 || $x == 38 || $x == 41 || $x == 44) { ?>

            <div class="clear"></div>
     <?php } ?>
    <?php $x++; ?>
    <?php endwhile; ?>
    <div class="clear"></div>
    </div><!--//content_inside-->

    <div class="clear"></div>
    <div align="center" class="load_more_cont"><?php next_posts_link(' ') ?></div>
    <?php wp_reset_query(); ?>                        

<?php echo category_description(); ?>

<?php get_footer(); ?>