This plugin will automatically rename the permalink every xx minutes, rotating through a list of permalink slugs the admin sets. For example, if a page starts out as http://site.com/1234 then you could set it to change every 5 minutes or every day to /wxyz, etc.
The plugin could be used for a “secret” url, like if you did a website scavenger hunt, or did not want people to share a private url. Lots of uses from games to privacy.