paulmac

WordPress allows posting via email, but must be told to check for emails. This is achieved by calling wp-mail.php using either a cron job, or by including a hidden iframe in your blog footer.
This plugin adds the iframe to the blog footer without editing the theme – updating your theme won’t break your ability to email in posts to WordPress.

Email Post Activation

Adds an iFrame to your blog footer to automatically activate any posts written by email.

yehudah

A unique anti-spam solution to help you fight spam in registration, comments, forms (Contact Form 7). 
When the user comment or using contact form 7 his comments or message will not sent or be visible until 
the user will press a unique link sent to him when he submited his message.
<h4>For Example:</h4>
Think like this i’m a spammer registering to your site, after register to your site i see a message about 
the need to activate my account, if i used fake email address this address will be blocked because it’s never 
activated, if i used a real address i activated my account with success ! 
Now i would like to change my email address so i can spam without getting any messages from your site but oops 
i can’t change my email address because the plugin blocking it ! 
Ok let’s try my luck and start spam in the commnets, posting my first comment and getting a message: 
“to see the comment you must approve your comment by pressing the link in your email address”.
I think you got the idea but what would happen if i will not press it the email and the ip address will be blocked because no one press the link, if i did press the link in the second on the third time YOU as site admin can block 
his ip and email address manually in the plugin options.
Plugin Features:
<ul>
<li>User activation by email.</li>
<li>Block user from changing is email address – EVEN BY ROLE !</li>
<li>Protect from spam commnets by sending unique url approve to the user email address – EVEN BY ROLE !</li>
<li>Auto learn mode – unverify users or comments will be deleted after time interval you choose.</li>
<li>Recaptcha protection for registration.</li>
<li>Recaptcha protection for login.</li>
<li>Recaptcha protection for commnets – EVEN BY ROLE.</li>
<li>Ban user from register or comment by ip or email.</li>
<li>Customise email notification to the users.</li>
<li>Import and export option to save plugin settings.</li>
</ul>

WASP – Anti Spam

A unique anti-spam solution to help you fight spam in registration, comments, forms (Contact Form 7).

Email Post Activation vs WASP – Anti Spam