Plugins

Show the current number of users in a line.

Set some default options for new user accounts.

Notify a user about when he sent comment or form via Contact Form 7

Replace the input field for adding existing users to a site with a more comfortable dropdown menu!

This widget creates simple list of existing users

WP User Timezone displays the front-end dates & times in the browser's local timezone without actually modifying your database.

Users that are NOT admins (subscribers, ..) are not allowed to modify their own profiles. "Profile" tab is removed from wordpress admin.

This plugin allows you to enable / disable the unused resources included by WordPress and third-party themes and plugins.

WP-Validate collects all the pages on your site and runs them through the W3C's HTML Validator.

WP Valid Email is a WordPress plugin which offers suggestions to users who mis-type their email address when entering it on your website.