Every time I have an exam, I show up to class and place my scan tron and number 2 pencil on my desk, in plain sight. This is perfectly normal for exams that require a scan tron, but in those that don’t it may cause people to run to the bookstore and then arrive once again ten minutes late, clearly exhausted.

Variations on this method:

• Show up with a blue book
• Show up with a clearly different scan tron
• Show up with an abacus

That last one may not cause anyone to run to the store, but it may cause them to have second thoughts about how they invested their studying time.