A WordPress plugin that creates and adds support for shortened urls plus the shortlink auto-discovery tag
The default settings should suit most people, but if there are a couple of things you can change should you wish. There are also a few tags you can use within your own pages.
If your domain name is a bit long and you own a smaller domain you would like to use as your shortened domain, you can add this in the settings page. You would then just need to make sure that the new domain pointed to the original via a ProxyPass setting.
There are many ongoing conversations on the web about how to describe shortened links in HTML. There appears to be no absolute right way, so by default if will be rev=canonical. Should you want to use another way, you can also change this via the settings page.
And finally... there are a couple of tags you can use in your own templates, that will return the short link for that page. You need to pass them the post ID.
<?php get_revcanonical_link($post->ID) ?> ===> Echo the shorturl to the screen <?php $url = revcanonical_link($post->ID) ?> ===> Assign the shorturl to a variable