wackey

This plug-in is Twitter “@Anywhere” API and “Topsy” API using. 
Visitor’s twitter account can be attested putting up connected button to the blog entry. 
After it attests it, link and blog owner’s following buttons and blog owner’s twitter profile can be displayed. 
Furthermore, the visitor takes side with the page by visitor’s account and it is possible to contribute. It is default and there are url on the page and blog owner’s twitter account. As a result, my account and blog URL will flow out on twitter, and the conversation extends.
<h3>Requirements</h3>
<ul>
<li>WordPress 2.9 or later</li>
<li>PHP 5.0 or later</li>
</ul>

Tw Anyware comment system

Add Twitter anyware API,connect and tweet,follow.And Topsy API using.It displays it like the comment column.

Miled

WordPress Social Login allow your website readers and customers to register on using their existing social accounts IDs, eliminating the need to fill out registration forms and remember usernames and passwords.
WordPress Social Login also allow you to import users contact list from Google Gmail, Facebook, Windows Live and LinkedIn.
WordPress Social Login gives you absolute control over users access to your website and comes a list of rules and restrictions for you to setup.
Easy to customize and integrate 
Wordpress Social Login come with a simple but flexible and fully customizable authentication widget. And if you are a developer or designer then you can customize it to your heart’s content.
Wide variety of providers 
Depending on the audience you’re targeting, you can choose from a wide variety of providers and services including: Social networks, Microblogging platforms, Professional networks, Media, Photo sharing, Programmers and Gamers networks.
Currently supported providers 
Facebook, Google, Twitter, Windows Live, Yahoo!, LinkedIn, Reddit, Disqus, Tumblr, Stackoverflow, GitHub, Dribbble, Instagram, 500px, Foursquare, Steam, Twitch.tv, Mixi, Vkontakte, Mail.ru, Yandex, Odnoklassniki, Goodreads, Skyrock, Last.fm, AOL and PixelPin.
Free, unlimited and white-label 
Wordpress Social Login is open-source and completely free. The source code is publicly available on <a href="https://github.com/hybridauth/WordPress-Social-Login" rel="nofollow ugc">GitHub</a> for anyone to help and contribute. You are free to use a WordPress Social Login in commercial projects as long as the copyright header is left intact.
Big thanks to everyone who have contributed to WordPress Social Login by submitting Patches, Ideas, Reviews and by Helping in the support forum.

WordPress Social Login

WordPress Social Login allow your visitors to comment and login with social networks such as Twitter, Facebook, Google, Yahoo and more.

Tw Anyware comment system vs WordPress Social Login