alfaguru

This plugin provides similar functionality to the <a href="http://drupal.org/project/sidecontent" rel="nofollow ugc">Drupal Side Content module</a>.
It enables you to define a set of widgets which are effectively placeholders. Each one is empty until you assign content 
to it when editing a page. 
This enables you to extend the content of the page into the sidebar.
Suppose, for example, you have a set of pages about people in your company. You could use a side content 
widget to add a biography for each of them, or a photo, or to list their favourite pizza toppings.
You can use the plugin without any template changes at all, but it does provide a simple API so you can test for the presence of side content widgets and adjust your templates accordingly.
As of release 0.7 of the plugin, it supports the <a href="https://codex.wordpress.org/Shortcode_API" rel="nofollow ugc">WP shortcode API</a>. There is also an extra add-on plugin which provides the same support for <a href="http://alexrabe.boelinger.com/wordpress-plugins/nextgen-gallery/" rel="nofollow ugc">NextGEN Gallery</a> shortcodes (development sponsored by <a href="http://www.comunicrea.com/" rel="nofollow ugc">Comunicrea s. n. c.</a>).
Release 0.75 fixes a bug affecting side content widgets with names containing characters other than lowercase alphanumerics. A new contributed extension provides integration with the qTranslate plugin.
Release 0.8 adds no new functionality but makes the plugin compatible with WP 2.7. 
Release 0.9 adds no new functionality but makes the plugin compatible with WP 2.8.1. 
Release 1.0 adds no new functionality but makes the plugin compatible with WP 4.1.0.
<h3>API</h3>
Use the following code to test for the presence of side content widgets:
<pre><code><?php if(function_exists('the_side_content') && the_side_content()->has_widgets() :?>
</code></pre>
Use the following code to test for the presence of a particular side content widget called ‘widget name’:
<pre><code><?php if(function_exists('the_side_content') && the_side_content()->has_widgets('widget name') :?>
</code></pre>
The plugin defines a filter, ‘side_content’, which can be used to preprocess side content widgets before display.

Side Content

Side Content enables you to create widgets which have different content on different pages.

interconnectit

Spectacula

With this page widget you can create a page in the normal WordPress editor and then drop it in any widget space – you can even embed shortcodes, videos and so on, all from the usual visual editor, rather than having to type HTML into a text widget.
And you can even control the widget to a significant degree, meaning it can be hidden and revealed as and when you require it.
This makes for a much easier to use process and has proven hugely popular with our users for the creation of profiles, sidebar videos and more.
And you no longer need admin access to be able to edit sidebar content belonging to you!
In a few rare cases, with poorly coded CSS in themes you may run into problems, so you should test this widget with your theme, across several browsers, before using it on a critical live site.
The widget will not show up on the page that is chosen to show in the widget. So if you click through to the page the widget will disappear from the sidebar.
If you want to translate the widget interface the files need for that are held in a sub-folder called lang. 
Just copy the spec-page-widget-en-US.po file to match your language (spec-page-widget-xx-XX.po) then load it up in poedit and change what you need to change.
If you create a translation and you’d like your language file included with the plugin contact us at <a href="http://spectacu.la/" rel="nofollow ugc">Spectacu.la</a> and we’ll see about adding it.
<h3>The install</h3>
<ol>
<li>Upload <code>spec-page-widget.php</code> and lang/. to <code>/wp-content/plugins/spec-page-widget/</code> or <code>/wp-content/mu-plugins/</code> directory. If the directory doesn’t exist then create it.</li>
<li>Activate the plugin through the ‘Plugins’ menu in WordPress</li>
<li>You should now see the widget show up under ‘widgets’ menu. Drop that widget into a sidebar.</li>
<li>With the widget in the sidebar you should see the config for this widget.</li>
</ol>
<h3>The config</h3>
<ol>
<li>First select the page you’d like to show.</li>
<li>If you want a title to show tick the show title option. This makes two more options available, ‘link title’ and ‘alternative title’. If you want to link to source or use another title enter them in this new area.</li>
<li>Next we have an option to use an excerpt rather than the full content. 
By default WordPress won’t let you create an excerpt for pages so one will be generated unless you’ve used another plugin to create an excerpt in which case that’ll be used.</li>
<li>Hide the page from the normal WordPress list of pages. 
This lets you to remove links to that page from other parts of WordPress that use the wp_list_pages() call. 
If you have two of these widgets both calling the same page then hiding the page in one will hide it in all.</li>
<li>Finally hit save.</li>
</ol>

Spectacu.la Page Widget

Widget that lets you output the content of a page in any place that'll accept a widget and allows you to hide said page from navigation (wp_list_ …

Side Content vs Spectacu.la Page Widget