It may be a weird case for having to regenerate $form['#token'] and $form['form_token'] in Drupal form API manually. But we had a use-case where the same form is presented to the user first as an anonymous user and later as an authenticated user.
Earlier I wrote a blog about different ways to reset admin password, one of those was using Drush. Sometimes you will need only momentary admin access to site. It happened recently to me when I had to deploy a new feature to live site but unaware of Drupal admin password, however I had command line access to server.
Drupal quiz module always wanted a provision to easily navigate from one question to other, given the limitation in existing version that quiz could display only one question at a time. This has been discussed several times in the quiz issue queue #842450: Quiz progress block would be really great. We came across a requirement where it was required for one of our potential clients a feature similar to that of Quiz progress block with more configurable options.