datumbox

The Machine Learning Antispam Plugin uses Machine Learning to detect spam and adult content comments and mark them as spam. Additionally it allows you to filter negative comments and keep them pending for approval.
It uses the Datumbox API 1.0v and is compatible with WordPress 3.6v or higher.
To read more about how it works, how it should be configured etc check out the original blog post: 
http://blog.datumbox.com/how-to-build-an-intelligent-antispam-wordpress-plugin/
<h3>Useful Links</h3>
Datumbox Website: http://www.datumbox.com/
Download API Documentation and Code Samples: http://www.datumbox.com/machine-learning-api/
Sign-up for free API Key: http://www.datumbox.com/users/register/
View your API Key: http://www.datumbox.com/apikeys/view/

Machine Learning Antispam

The Machine Learning Antispam Plugin uses Machine Learning to detect spam and adult content comments and mark them as spam.

cmwslw

<ul>
<li>Get Credit button pops-up an interface detailing the credit just earned.</li>
<li>[In Works] Get Credit button can trigger auto-generated quiz for additional interaction.</li>
<li>[Planned] Auto-tag articles with credit that can be earned.</li>
<li>Simple, one-minute installation.</li>
</ul>

Fireplug-in

The Official Wordpress Fireplug-in. Allow your readers to get credit for visiting your website and reading your content.

Machine Learning Antispam vs Fireplug-in