FeedDelay Wordpress Plugin - Rating, Reviews, Demo & Download
Plugin Description
Allows you to publishe posts with a delay in your feed. You can set a different delay for each feed type as there are RSS1, RSS2, ATOM and RDF.
As an extra this plugin gives you the possibilities to remove the Wordpress version from your feeds and you can disable/enable each feed type. (This is not working in very old Wordpress version like 2.0.x)
Visit the Plugin Homepage for more details.