Random Custom Post

<?php
            $custom_post = new WP_Query();
            $custom_post->query('post_type=testimonial&showposts=1&orderby=rand');
?>
 
<?php while ($custom_post -> have_posts()) : $custom_post -> the_post(); ?>
 
                <div class="post_type">
 
                        <?php the_content();?>
 
                        <span class="name right clear">
                                <?php echo get_post_meta($post->ID, 'custom_post_type_name', $single = true); ?>
 
                                <?php echo get_post_meta($post->ID, 'custom_post_type_title', $single = true); ?>
 
                        </span>
 
                </div>
                <?php endwhile; ?>