alvaron

Create a dynamic gallery multiple widget(works as shortcode too), with thumbnails of each post with youtube/vimeo(beta) videos displayed on the content linked to the post single. Checks all you video posts, but you can filter them by category and choose the number of posts.
Based on
Media Library Gallery 1.0.2 (http://www.cybwarrior.com/media-library-gallery/) by Raphael Verchere(http://www.cybwarrior.com)
Video Thumbnails 1.0.7(http://sutherlandboswell.com/2010/11/wordpress-video-thumbnails/) by Sutherland Boswell(http://sutherlandboswell.com)
and
Simple Video Embedder(http://www.press75.com/the-simple-video-embedder-wordpress-plugin/) by James Lao(http://jameslao.com/)
Special thanks to Felipe Caroé http://www.felipecaroe.com/ for suggesting the name!
<h3>Arbitrary section</h3>
This Plugin supports YouTube and Vimeo(beta) 
If you decide to use iframe and embed object, please use the html code insert on the post 
The plugin works better when urls are pasted on the post editor
This readme file were validated at https://wordpress.org/extend/plugins/about/validator/

YouTubeNails

Create a dynamic gallery multiple widget(works as shortcode too), with thumbnails of each post with youtube/vimeo(beta) videos displayed on the conten …

voceplatforms

Chris Scott

Adds multiple post thumbnails to a post type. If you’ve ever wanted more than one Featured Image on a post, this plugin is for you.

Multiple Post Thumbnails

Even though this plugin hasn't been updated in a long time, it still works great! So I guess there's just no reason for the developer to have it updated. ;-)
For me this plugin is one of the easiest ways to selectively add a header image. I want it on some pages, but not on others. Using the standard Featured Image function will set it foor all or none, so that's not flexible enough.
One suggestion for an update though:
Now you still need to add the following snippet to your theme's function.php.
if (class_exists('MultiPostThumbnails')) {
    new MultiPostThumbnails(
        array(
            'label' => 'Secondary Image',
            'id' => 'secondary-image',
            'post_type' => 'post'
            'post_type' => 'page'
        )
    );
}
It would be great if the plugin did this automatically. That will also keep the plugin active if you switch themes. 
P.S.
To add the meta box to other post types, just add it to the snippet.
'post_type' => 'event' will add it for Events Manager, for example. ;-)



Still works great!

Adds multiple post thumbnails to a post type. If you've ever wanted more than one Featured Image on a post, this plugin is for you.

YouTubeNails vs Multiple Post Thumbnails