ShinichiN

This plugin adds a widget to display furture scheduled posts list on your sidebar. You can specify how many posts to be listed.
<ul>
<li><a href="https://github.com/ShinichiNishikawa/Widget-of-the-Future" rel="nofollow ugc">GitHub</a></li>
<li><a href="http://nskw-style.com/2013/wordpress/plugin-downloads/Widget-of-the-Future.html" rel="nofollow ugc">Plugin Homepage</a></li>
</ul>
<h4>Title and post counts</h4>
In the widget page, you can specify the title and the number of posts.

Future Widget

This plugin adds a widget to display furture scheduled posts list on your sidebar. You can specify how many posts to be listed.

Adam Erstelle

This plugin allows a wordpress administrator to schedule an additional css file to display on the website for holidays or special events for all visitors.
The css file will be added to the live site. Great for setting a Christmas theme!
If you just want to have a theme loaded instead of just a css file, check out the wp-scheduled-themes plugin.

WP Scheduled Styles

Schedule a css file to display on the live site for holidays or special events. (Available from Appearance - Scheduled Styles)

Future Widget vs WP Scheduled Styles