WPReady

The plugin works similar as shortcodes with important differences:
<ul>
<li>It looks for any tag in the post with the following format: {cf your_custom_field_name=your_custom_field_value}</li>
<li>For any tag found, it create a custom field for that post.</li>
<li>The tag is erased from the post.</li>
</ul>
<h4>How to use</h4>
Type in anywhere in a post: 
{cf your_custom_field_name=your_custom_field_value}
Examples:
<ul>
<li>{cf thumbnail=http://wordpressready.com/wp-content/uploads/oneringtorulethemall.jpg}</li>
<li>{cf posticon=/wp-content/uploads/posticon.ico}</li>
<li>{cf my_custom_color=#22fb30}</li>
</ul>
This three examples written inside the post will create three custom fields with respectives values 
when you publish the post. 
After publishing, the tag inside the post are deleted. No other information is erased.
<h4>Notes</h4>
<ul>
<li>Because the way the plugin works, it will run fine with ANY desktop blogger(Windows Live Writer, Scribefire, Qumana, w.Bloggar, Zoundry 
, Thingamablog, Blod Desk, Flock, Post2Blog, Bleezer, you name it)</li>
<li>The plugin can be used even inside the wordpress editor (though what would it be the point?)</li>
<li>You can use any number of custom field for post. </li>
<li>Reserved characters: ‘{cf’ and ‘}’,because it conflicts with the delimiters.</li>
<li>After the post, the tags are automatically erased.</li>
<li>If the custom field is already present, its value will be replaced.</li>
</ul>

Text to Custom Field

Allows adding custom fields from ANY desktop blog editor even if the editor can't support custom fields!

toxnico

Did you ever feel like your website or blog login page is ridiculously fragile and reachable, and could be easily broken in by an intruder?
Personally I hate to think of hundreds of people playing with my door lock hundreds of times a day. It’s the same with my blog login page.
On WordPress, there are two main potential vectors of bruteforce intrusion: 
* http://my-site.com/wp-login.php, which is the login page 
* http://my-site.com/xmlrpc.php, which is an API gateway for interacting with third party applications.
This plugin adds one security layer in front of your login page, and by the way you can also disable XML-RPC with a simple checkbox if you don’t need it (XML-RPC is a WIDELY used vector of attacks).
The idea is simple: you choose a pair of words, and when you want to access your login page, you just have to provide them in the URL like this: http://my-site.com/wp-login.php?word1=word2. That’s all! 
If you try to access your login page without this pair of words, you get a configurable error message, where you can insult the attacker as much as you want 😉

WP Login Door

This plugin is the easiest way to hide your login page and thus avoid brute force attacks



Simple and useful

Adds a secret URL key to access the login page and lets you disable XML-RPC, protecting against bruteforce attacks.

Text to Custom Field vs WP Login Door