WordPress.org

Shuffle modifies/improves your Media Library in a number of ways. Shuffle lets you:

1. Attach an item (Image, Audio, Video) to anything (Post, Page, Custom Post Type, another Attachment)!
2. Reorder an item's attachments using a simple Drag and Drop UI
3. Detach an attachment from an item without deleting the attachment
4. View all attachments attached to an item

All of these things should already be in WordPress... but they're not!

This plugin is especially useful if you are using WordPress as a CMS and/or have a media-heavy site.

Use these functions in your Theme to get your re-ordered Media:

<?php 
//In the Loop:
get_images();

//Outside of the Loop:
get_images( get_the_ID() );

// Audio
get_audio();

// Video
get_video();

?>

Read more: http://scotty-t.com/2010/11/15/my-first-plugin-shuffle/