TIgor4eg

Plugin shows <a href="http://www.twitter.com" rel="nofollow ugc">twitter</a> links from <a href="http://backtweets.com" rel="nofollow ugc">backtweets.com</a> in widget area.
<a href="http://tigor.org.ua/wp-twitbacks/" rel="nofollow ugc">Russian description</a>
It shows “shortened” links like bit.ly, goo.gl and other link shortering services.
You can configure your widget.

WP Twitter Backlinks

Plugin shows twitter links from backtweets.com in widget area.

hswplugins

Post Curator is a do follow link directory. Fully automatic, it will periodically check your blog for new posts and link to them. How Post Curator works.
<ol>
<li>Go to Settings > Post Curator.</li>
<li>Choose the most appropriate category for your blog.</li>
<li>Click the button to register your blog with our servers.</li>
<li>Click Save.</li>
</ol>
To display the link to your blog we take the Title of the post, a 250 character preview from the content, the URL for the featured image and any tags. We do not show the content of the post, just enough info to create a decent listing and entice some clicks for you. We will add new links to your content at a rate of about 1 per day.
Automated link submissions to Post Curator are free.

Post Curator – Zero Effort SEO Backlinks

Get zero effort do follow backlinks to your blog posts with Post Curator. Add this plugin and we will automatically link to your content for free.

WP Twitter Backlinks vs Post Curator – Zero Effort SEO Backlinks