And there’s as a whole load of other elements you can remove as well.

<?php
<code>remove_action( 'wp_head', 'feed_links_extra', 3 ); // Removes the  links to the extra feeds such as category feeds
remove_action( 'wp_head', 'feed_links', 2 ); // Removes links to the  general feeds: Post and Comment Feed
remove_action( 'wp_head', 'rsd_link'); // Removes the link to the Really  Simple Discovery service endpoint, EditURI link
remove_action( 'wp_head', 'wlwmanifest_link'); // Removes the link to  the Windows Live Writer manifest file.
remove_action( 'wp_head', 'index_rel_link'); // Removes the index link
remove_action( 'wp_head', 'parent_post_rel_link'); // Removes the prev  link
remove_action( 'wp_head', 'start_post_rel_link'); // Removes the start  link
remove_action( 'wp_head', 'adjacent_posts_rel_link'); // Removes the  relational links for the posts adjacent to the current post.
remove_action( 'wp_head', 'wp_generator'); // Removes the WordPress  version i.e. - WordPress 2.8.4</code>
?>

Original article here: http://rjpargeter.com/2009/09/removing-wordpress-wp_head-elements/