KaeruCT

This plugin allows passwords for password-protected pages/posts to be passed directly through the URL.
The query string parameter that should contain the password is <code>pw</code>.
For example, if the URL of your post is <code>http://myblog.com/password-protected-page/</code> and the password is <code>PASSWORD</code>, 
then just append <code>?pw=PASSWORD</code> to it.
If the URL already contains a query string (for example, <code>http://myblog.com/?p=5</code>), then be sure to append <code>&pw=PASSWORD</code> instead.

Password Passthrough

This plugin allows passwords for password-protected pages/posts to be passed directly through the URL.

Aubrey Portwood

Small script that removes Protected: and Private: from titles of posts and pages that are password protected and private.
<h3>Development</h3>
This plugin is developed over at <a href="https://github.com/aubreypwd/remove-protected" rel="nofollow ugc">Github</a> if you want 
to contribute.

Remove Protected

Small script that removes Protected: and Private: from titles of posts and pages that are password protected and private.

Password Passthrough vs Remove Protected