Wp Like Box widget for WordPress is a social plugin that enables Facebook Page owners to attract and gain Likes from their own website.
more info :
http://wp-plugins-themes.com/wp-plugin/wp-facebook-fan-box-widget-easy-wp-plugin/
The Like Box enables users to:
1.See how many users already like this Page, and which of their friends like it too
2.Read recent posts from the Page
3.Like the Page with one click, without needing to visit the Page
4.No api key or application id, just url to you facebook fan or ap page.