gentlesource

This plugin creates a short URL from the blog post permalink and stores it 
in the database. The URL is displayed below the blog post along with a link 
to twitter that passes the short URL on.
You can use all short URL services that offer an API. Here are a few:
<ul>
<li>http://melt.li/</li>
<li>http://lin.io/</li>
<li>http://unrelo.com/</li>
<li>http://bit.ly/</li>
<li>http://u.nu/</li>
<li>http://tinyurl.com/</li>
</ul>

GentleSource Short URL

Automatically shortens the blog post URL.

llvllagic_l3oy

Monetize your WordPress website/blog with XIP.ir shortlinks. This plugin converts your links to XIP.ir links automatically.
You will able to:
<ul>
<li>Enable/Disable XIP.ir feature</li>
<li>Convert either all links or only outgoing links to XIP.ir</li>
<li>
Choose ad type: Interstitial or Banner ad
You will need an XIP.ir id. To get it, login to XIP.ir go to http://XIP.ir/referrals.php and find ?r=xxxx. 
xxxx is your XIP.ir ID.
</li>
</ul>

XIP WordPress Plugin

Monetize your WordPress website/blog with XIP.ir shortlinks. This plugin converts your links to XIP.ir links automatically.

GentleSource Short URL vs XIP WordPress Plugin