John Godley

Sniplets is a generic text insertion plugin with support for an extensible processing framework. At it’s simplest this means you can dynamically replace text in your posts with text that may be defined elsewhere, or created by some other module. For example, you can use Sniplets to perform syntax highlighting of files, execute custom PHP code, insert data from a database, and perform all manner of other useful tasks within a standard interface.
<ul>
<li>Replace tags in a post with pre-defined text</li>
<li>Apply processing functions to the pre-defined text to perform additional functionality</li>
<li>Automatic insertion – data can be made to automatically appear in various places (header, footer, before post, after post, more tag, initialization)</li>
<li>Custom processors can be written by the user</li>
<li>Fully localized</li>
</ul>
Sniplets is available in:
<ul>
<li>English</li>
<li>Belorussian thanks to Marcis Gasuns</li>
</ul>
<h3>Documentation</h3>
Full documentation can be found on the <a href="http://urbangiraffe.com/plugins/sniplets/" rel="nofollow ugc">Sniplets</a> page.

Sniplets

Sniplets is a generic text insertion plugin.  Use it to manually or automatically insert data, PHP, syntax highlight, and almost anything else!

Dekisugi

This “Insert Footnote” plugin add any text or HTML code at the bottom of all post contents. If you are tired of text-insertion plugins that is just too bulky and complicated, this simple and light plugin is ideal for you. Javascripts such as adsense codes can also be added.
The nice thing about this plugin is you don’t get extra blank lines above and below your custom footnote, therefore looks nicer on your posts. Visit <a href="http://dev.coziplace.com/free-wordpress-plugins/insert-footnote" rel="nofollow ugc">Official</a> page.

Insert Footnote

This plugin add custom texts/HTMLs/scripts below all post contents. This plugin is so light.

Sniplets vs Insert Footnote