SISCOM WEB DESIGN

This is a simple plugin without any hassles, it automatically adds the Google Plus One Button to your WordPress posts and pages. 
There is no admin for this plugin since everything is done automatically, just upload the plugin , activate it and it will add the necessary code for the Google +1 Button to appear on every post and page. 
The Button will be located at the Top-Right Corner Inline with your posts.
Features:
<ul>
<li>Automatically included on Posts</li>
<li>Automatically included on Pages</li>
<li>Button location is at the Top-Right Corner Inline With the Text</li>
<li>Simple enough, Does not slow down your site, Does not mess up other plugins</li>
</ul>

WP PlusOne This

The WP PlusOne This plugin, automatically adds the Google Plus One ( +1 ) Button to your WordPress posts and pages.

Jaspreet Chahal

This plugin gives you control to initially hide part of your article from user. Content is displayed correctly once user Facebook Like or +1 your page
Usage: Warp your content in [ltu][/ltu] tag. You are able to use this tag once in your post. Make sure that plugin is active and enabled.
Make sure that you’ve created a Facebook App ID
To check out other plugins by me please visit http://jaspreetchahal.org
To Upgrade to PRO version 
visit http://jaspreetchahal.org/wordpress-like-to-unlock-content-plugin/

Like to Unlock lite

This plugin gives you control to initially hide part of your article from user. Content is displayed correctly once user Facebook Like or +1 your page

WP PlusOne This vs Like to Unlock lite