What are your top 5 wordpress plugins you like to use?

My favourites are:

WordPress SEO - http://yoast.com/wordpress/seo/
Akismet - http://akismet.com/
Broken Link Checker - http://w-shadow.com/blog/2007/08/05/...for-wordpress/
WP to Twitter - http://www.joedolson.com/articles/wp-to-twitter/
NextGEN - http://alexrabe.de/wordpress-plugins/nextgen-gallery/