Peter

Adds shortcodes [blogurl], [posturl], [templateurl], and [childtemplateurl] for WordPress 2.6 and up. Use [blogurl] to generate your site URL. It offers the parameters “slash” and “noslash” (to add a trailing slash; [templateurl] and [childtemplateurl] also support this), as well as “uploads” to produce the URL of the uploads folder and “wordpress” to produce the URL of your WP files. Use [posturl id=3] (replace “3” with a post ID) to generate the permalink for any post.
<h4>Features</h4>
<ul>
<li>
[blogurl] will generate <code>http://www.yoursite.com/</code>
</li>
<li>
[blogurl wordpress] will generate the URL to the root of your WordPress files, if they are in a different location than your site root
</li>
<li>
[blogurl noslash] will generate <code>http://www.yoursite.com</code>
</li>
<li>
[blogurl uploads] will generate <code>http://www.yoursite.com/wp-content/uploads/</code>
</li>
<li>
[blogurl uploads noslash] will generate <code>http://www.yoursite.com/wp-content/uploads</code>
</li>
<li>
[posturl id=375] will generate the correct permalink for the post with an ID of 375; for example, <a href=”[posturl id=375]”>post about this plugin</a> would generate <a href="http://www.theblog.ca/blog-url-shortcodes" title="From Peter's Useful Crap" rel="nofollow ugc">post about this plugin</a>
</li>
<li>
[templateurl] will generate the URL to your parent theme’s root
</li>
<li>
[childtemplateurl] will generate the URL to your child theme’s root
</li>
</ul>
<h4>Requirements</h4>
<ul>
<li>WordPress 2.6 or higher</li>
</ul>

Peter’s Blog URL Shortcodes

Use shortcodes for blog URLs, post URLs, and template URLs so that your posts always have the correct internal links.

mainsufian

Now its easy to change domains and move your wordpress blog from subdomain to parent domain like from localhost to live domain you just need to use this shortcode [base_url] as your base url and images So now all links and images are fine after transfer site from localhost to live you don’t need to adjust links after change domain.
ShortCode 
[base_url]

Relative URL ShortCode

This Plugin is Best when you need to work on test domain like localhost or on some sub domain and you need to move data or transfer complete site then it's best to keep links fine.



shift content then very useful

Now its easy to change domains and keep links and images fine you just need to use this shortcode [base_url] as your base url for links and images.

Peter’s Blog URL Shortcodes vs Relative URL ShortCode