I did search for this, but it is hard to know what others may have called this feature I'm looking for.  We call it the "Time Machine" feature.

I've worked on other sites in the past where we've implemented a feature where we can specify the date we want to render the site for.  This allows us to make changes to the site that won't go live for another couple of weeks, but our clients can check out and review those changes by specifying a parameter in the URL.

That's how we do it now.  Page at a time.  It works but...

What I'd like to see in DNN is a feature that would allow us to let people with specific roles set the date they want to render the site for in a toolbar similar to (or maybe the same toolbar) as the admin toolbar.

With the current functionality that I'm aware of, in order for our clients to be able to see what the site is going to look like in the future, we have to setup a staging site where we make the changes and then copy stage to production when the new site is approved.

So my question is, does this feature exist some place that I'm not aware of?  If it doesn't exist, what would it take to implement this feature short of changing the system clock on the server?  Seems to me we would need an API that everything pulls the date/time from to determine which pages and modules to display and some gui to override the current date/time.  Maybe the API already exist?  (wishful/hopeful thinking).