<?php global $wpdb; $numposts = 40;
            $rand_posts = $wpdb->get_results("SELECT * FROM $wpdb->posts WHERE post_status = 'publish' AND post_type = 'post' AND  post_category != 1 ORDER BY RAND() LIMIT $numposts");
            foreach($rand_posts as $post) : setup_postdata($post);

            $title = $wp_query->post->post_title; $str = strtolower($title); $newtitle = str_replace(" ", "-", $str); ?>
            <a href="<?php the_permalink() ?>" title="<?php the_title(); ?> Wallpaper"><img src="<?php echo get_option('siteurl'); ?>/images/160x120/<?php echo $newtitle ?>.jpg" alt="<?php the_title(); ?>" /></a>
            <?php endforeach; ?>