Märt Rang

This plugin adds new shortcode: [shortcode_ajax][/shortcode_ajax] 
Originally written for WP-Table Reloaded plugin to add ability reload some tables dynamically. It should work with other plugins too!

Shortcode Ajax

Easiest solution to add some ajax to shortcodes.

Doyle Lewis

Use this plugin to create and manage polls you can put anywhere on your site with a widget. Features:
<ul>
<li>Widget for placing polls</li>
<li>[bsp_show_results] shortcode for displaying poll results</li>
<li>Easy administration of new polls and options</li>
<li>Fully translatable</li>
</ul>

BuyHTTP Super Polls

Easily create and manage polls for your site. Then display results in a post or page.

Shortcode Ajax vs BuyHTTP Super Polls