It would be great for WordPress to have a Date Range on the Publish settings on Posts.
For example Publish this post ON 08/01/11 and UNPUBLISH on 08/03/11
Essentially removing if from the site, public view, archives etc. but still accessible to admin on the Dashboard. No need to archive a post for public view if it no longer applies, just UNPUBLISH it.
A bulk version of this would be great too.
These posts: publish from this date to that.
These posts: publish from this date to that
and so on.
basically giving a post a start date and an expiration date