Sharaz Shahid

Code Widget is simple widget allows you to insert any arbitrary Text/HTML and run PHP Code or Short Code. This Widget parses PHP code into simple text and much more.
Only users with the unfiltered_html role will be allowed to insert unfiltered HTML. This includes PHP code, so users without admin or editor permissions will not be able to use this to execute code, even if they have widget editing permissions. 
This plugin is developed and maintained by <a href="https://twitter.com/sharazghouri1" rel="nofollow ugc">Sharaz Shahid</a>

Code Widget

Code widget help  to  add  Short Code, PHP Code, HTML, and Simple Text in widget.

cgarvey

Sometimes you want to put the base URL (that of the blog, or that of the active template) in your content editor. Times when the template customising isn’t quite flexible enough. 
With this plugin you can use [url_base] to output the base URL of the blog (as set in your Settings). Or, you can use [url_template] to output the URL of the active template.
For example <code><img src="[url_base]/test.png /></code> in your editor might output <code><img src="http://localhost/wordpress/test.png" /></code> (if http://localhost/wordpress is what you have configured as your blog URL in Settings).
The supported short codes are as follows: 
* [url_base] – the configured blog URL (set in Settings). E.g. http://localhost/wordpress 
* [url_template] – the URL of the active template. E.g. http://localhost/wordpress/wp-content/themes/mytheme1
<h3>License</h3>
This plugin uses the GPLv3 license.

URL ShortCodes

URL ShortCodes plugin adds support for a basic short codes to use in your post/page editor that produce correct absolute URLs.

Code Widget vs URL ShortCodes