Change WordPress Login Logo

This snippet allows you to change the logo you see when you login to WordPress(http://website.com/wp-admin).

<?php
function custom_login_logo() {
    echo '<style type="text/css">
        h1 a { background-image:url('.get_bloginfo('template_directory').'/images/my-custom-login-logo.png) !important; }
    </style>';
}
add_action('login_head', 'custom_login_logo');
?>