In theory you may be able to do something with CTA Featured Threads or similar and User Upgrades.
e.g. they could purchase a user upgrade which promotes them into a group that is allowed to feature their own threads.
This would, however, still require some level of manual management. First, there'd potentially be no way of restricting how many threads a user could feature, further there would likely be no way of setting a specific feature date.
Other than that, I'm not aware of a specific add-on that currently exists.