galaxiusmons

This allows you to quickly create a unique sidebar for any post, page, category page or for all posts belonging to a category. You simply enter a name for the sidebar when you create or edit a post, page or category. Browse to Appearance -> Widgets, find your new sidebar and add some widgets to it.

Galaxius Custom Sidebars

Allows quick creation of unique sidebars for posts, pages and categories.

Kirsty Burgoine

Features Include: 
The ability to add video directly in to a page, post or any of your own custom post types using the video URL (not the embed code) and a Short code.
Fully responsive so will fill the width of the containing area and scale depending on screen size. No need to set a width and height, just set the width of the div your content sits in.
Support for custom post types. Automatically adds your custom post types to the settings screen so that you can choose which you would like to be able to add video to.
Multi instance responsive Widget to allow you to add videos to multiple widget ready areas.
<h4>Requirements</h4>
<ul>
<li>WordPress 3.0 + with WordPress Widgets</li>
</ul>

Responsive Video

This widget will display a Responsive YouTube or Vimeo video in pages / posts and sidebars.

Galaxius Custom Sidebars vs Responsive Video