Sean Fisher

This plugin will hide WordPress Admin (/wp-admin/) when a user isn’t logged in. If a user isn’t logged in and they attempt to access WP Admin directly, they will be unable to and it will return a 404. It can also rename the login URL.
Also, you can add HTTP authentication directly from WP Admin and add custom username/password combinations for the HTTP auth or use the WordPress credentials.
This doesn’t touch any .htaccess files or change the WordPress core files. All the CSS/Images under /wp-admin/ are still accessible, just not the .php ones.
If you enable HTTP authentication, it will add HTTP authentication to the PHP files in /wp-admin/.
To contribute to the development, check out <a href="https://github.com/srtfisher/Lockdown-WPAdmin" rel="nofollow ugc">the GitHub Repository</a>.

Lockdown WP Admin

Lockdown WP Admin conceals the administration and login screen from intruders. It can hide WordPress Admin (/wp-admin/) and and login (/wp-login.

Arevico

The fundamentals of securing your website. We believe in fixing security issues at the root, while keeping user convenience high. Arevico basic security helps you by:
<ul>
<li>requiring associated email to use as a login username</li>
<li>Enforce strong password</li>
<li>Enforce reset of weak passwords</li>
<li>Enforce password expiration after a specified amount of days</li>
<li>Hide or customize login error message</li>
<li>Lockout an account after too may failed login attempts</li>
<li>Send an email with a reset link to the email associated with the locked account.</li>
</ul>
You can determine which options you want to set in the admin menu.
Requirements
<ul>
<li>PHP5</li>
<li>Network site compatible</li>
</ul>
We plan on adding more security features. So be sure to <a href="http://arevico.com/support/" rel="nofollow ugc">contact us</a> if you have a great idea.

Arevico Security Basic

Secure your website with account lockdown, limited attempts, enforcing strong passwords and much more! Fix issues at the root, without user inconvenie …

Lockdown WP Admin vs Arevico Security Basic