A good plain radiograph to assess the skill of a reporter, not least when reporting high volumes of radiographs per hour as is typical in professional practice rather than professional exams.

This was a T4 lung cancer, so advanced in local staging but easily missable in a stack of 500 unreported plain radiographs.

The hilum is a review area for a reason: it can be very tricky.

The contemporary radiologist should act with prudence, separating potentially concerning radiographs requiring CT and not flooding the CT scanner with endless unnecessary investigations with all that it entails in terms of radiation exposure, anxiety to the patient, practical inconvenience, and cost. 

I use this in a fellowship rapid reporting or viva exam every time.