File Permissions & Size Check is a WordPress plugin by wycks that will add a little “x” next to any files/folders set to 777, since this is inherently insecure. Checks all recursive folders that come with a default WordPress install.
Checks root, wp-admin, wp-content, wp-includes and all sub folders
Includes your plugin and theme folders
Ignores images, text and CSS files
Requires PHP 5.1.2 or greater
This plugin can be CPU intensive as it iterates over your whole folder/file structure to gather statistics. The author suggests you run this during low traffic.
Download and info: http://wordpress.org/extend/plugins/wp-file-permission-check/
