atitan

Math Quiz generates dynamic math problem in the comment form to beat spam robots and supports flexible form style customization.
Demo website: https://atifans.net/ (with Supercache and AJAX comment form enabled)
For PayPal donation, please use this email address: info a.t atifans.net
Features:
<ul>
<li>Dynamic problems prevent spam robots from posting unwanted content.</li>
<li>Quiz form inserted using AJAX for better compatibility with HTML cache plugins.</li>
<li>Form style and position can be customized in the control panel.</li>
<li>Trackbacks and Pingbacks are checked with DNS queries to avoid abuse.</li>
<li>Optional login page protection.</li>
</ul>
Translators:
<ul>
<li>SLV-es (Spanish)</li>
<li>Joao Paulo (Portuguese)</li>
</ul>

Math Quiz

Math Quiz generates dynamic math problem in the comment form to beat spam robots.

Noname

!!! IMPORTANT !!! 
If you have used the old Geo-Captcha plugin please completly uninstall it (the form is on the main page of the plugin) 
and remove the plugins files. Geo-Captcha & Geo-Blacklist ist fully based on the old Geo-Captcha plugin but is not 
compatible with it and uses new names for options and databases! 
!!! IMPORTANT !!!
There are a lot of ways to prevent spam. One that is still pretty often used is to let your readers type a code from a 
captcha image to a textbox. Geo-Captcha uses the same technic but you can define a whitelist with countries. People from 
this countries will not be forced to enter the captcha code. You can also define a blacklist which prevents people from 
some countries from posting any comments.
The location of the visitors is checked using the GeoLite Country-Library from MaxMind (http://www.maxmind.com). 
The captcha image is generated using SecurImage from drew010 (http://www.phpcaptcha.org).
<ul>
<li><a href="http://plugins.deformed-design.de/" rel="nofollow ugc">Plugin Page</a></li>
<li><a href="http://support.deformed-design.de/" rel="nofollow ugc">Plugin Support</a></li>
</ul>

Geo-Captcha & Geo-Blacklist

Geo-Captcha shows a captcha image only to countries you don't trust. Geo-Blacklists allows you to disable comments for some countries.

Math Quiz vs Geo-Captcha & Geo-Blacklist