andeggs

ProSocial is a free WordPress plugin which connects your readers with your authors.
It shows an attractive pop-up bar next to your authors’ names, with links to their social media accounts.
On multi-author blogs, it’s a great way of encouraging your readers to connect with your authors on other social networks.
See it in action here: http://digitalshift.me/prosocial/
Features:
<ul>
<li>40+ social networks: You choose which networks to display. Your authors can add then their accounts themselves.</li>
<li>Includes email: Show your authors’ email addresses as well (with a captcha form to prevent spam).</li>
<li>Google Analytics: If you use Google Analytics, you can see who’s clicking on what.</li>
</ul>

ProSocial

ProSocial shows a pop-up bar next to your authors' names, with links to their social media accounts.

ifkooo

Put all social network in one login box for your blog.
Collect all users to your Email Invest account and send free promotions or bulletins to them.
<h3>One Login API</h3>
This PLUGIN require a API Class file from One_login to make connections between your blog and your one-login account.

One-Login

All networks in one box to login in your blog

ProSocial vs One-Login