Fumiki Takahashi

TAROSKY INC.

You can enter expiration date on edit screen. 
This plugin runs cron every minute to search expired posts and make them <code>private</code>.

Taro Clockwork Post

A WordPress plugin to expire post with specified date.

Marco Alluvion

The Media Expirator plugin allows users to set expiration dates for media library items. When the date is reached, the file will be automatically delete from the media library.
User can enable/disable expiration date for each media items directly in media editor.
This plugin is translatable.
<h3>Note</h3>
How to: 
Enable/Disable and set an expiration date for each items directly in WordPress media editor.
Goals: 
√ add enable/disable option 
√ plugin translatable 
√ add translations 
• create option page 
• enable time 
• time zone option 
• media types option 
• optimize code 
• ..add other ideas

Media Expirator

It works!

Media Expirator plugin allows users to set expiration dates for media library items.

Taro Clockwork Post vs Media Expirator