Purab

Facebook, Twitter, Google Plus and LinkedIn Share buttons.
The CSS Share Buttons easily allows your blog to be shared. Speedup you site with this share plugin.
<h4>Super Fast</h4>
This plugin is very light weight. As comapred to other Share button plugin This plugin is super fast.
We compared with all famous share button plugin. Our Plugin load CSS from CDN.
It show very lite share button only with HTML and CSS. 
It does not load any javascript like other 
We load only one CSS file with this plugin – only 1.5kb css file
<a href="http://wpapi.com/fastest-minimal-css-social-share-button-wordpress-plugin/" rel="nofollow ugc">Step by step installation instructions >></a>
FEATURE::
<ol>
<li>
Share with Facebook.
</li>
<li>
Share with Twitter.
</li>
<li>
Share with LinkedIn.
</li>
<li>
Share with Google Plus.
</li>
<li>
Floating Sidebar
</li>
<li>
Responsive Design
</li>
</ol>
<h4>Following is Demo URL for CSS Share Button:</h4>
http://wpapi.com/improve-blog-websites-readability/
Tested upto 4.0
<a href="http://wpapi.com/contact/" rel="nofollow ugc">Click here for customer support >></a>
<h4>Functionality</h4>
<ul>
<li>New – CSS Share Buttons. Integrates the ability to share your post with one click.</li>
</ul>
<h3>Help</h3>
For help and support please contact us at contact [at] wpapi.com
<h4>Following is Demo URL for CSS Share Button:</h4>
<a href="http://wpapi.com/contact/" rel="nofollow ugc">Click here for customer support >></a>

CSS Share Buttons

Facebook, Twitter, Google Plus and LinkedIn Share buttons. Super Fast Loading, No Javascript, Only CSS. Responsive Design, Floting Sidebar Option

Paul Ryan

jojaba

the_elusive

Anil Natha

pkarjala

Eduardo Larequi

Authorizer restricts access to a WordPress site to specific users, typically students enrolled in a university course. It maintains a list of approved users that you can edit to determine who has access. It also replaces the default WordPress login/authorization system with one relying on an external server, such as Google, CAS, LDAP, or an OAuth2 provider. Finally, Authorizer lets you limit invalid login attempts to prevent bots from compromising your users’ accounts.
View or contribute to the plugin source on GitHub: <a href="https://github.com/uhm-coe/authorizer" rel="nofollow ugc">https://github.com/uhm-coe/authorizer</a>
Authorizer requires the following:
<ul>
<li>CAS server (2.x, 3.x, 4.x, 5.x, 6.x, or 7.x) or LDAP server (plugin needs the URL)</li>
<li>PHP extensions: php-ldap, php-curl, php-dom</li>
</ul>
Authorizer provides the following options:
<ul>
<li>Authentication: WordPress accounts; Google accounts; CAS accounts; LDAP accounts; OAuth2 accounts</li>
<li>Login Access: All authenticated users (all local and all external can log in); Only specific users (all local and approved external users can log in)</li>
<li>View Access: Everyone (open access); Only logged in users</li>
<li>Limit Login Attempts: Progressively increase the amount of time required between invalid login attempts.</li>
<li>Shortcode: Use the <code>[authorizer_login_form]</code> shortcode to embed a wp_login_form() outside of wp-login.php.</li>
</ul>

Authorizer

Integrates nicely with Google hosted domain/s. Couldn't be happier with how it works!

Integrates well with Google Logins

I've experimented this plugin on a multisite and everything works pretty well.

Works great even on a multisite setup

Authorizer limits login attempts, restricts access to specific users, and authenticates against external sources (OAuth2, Google, LDAP, or CAS).

CSS Share Buttons vs Authorizer