A guy with his masters in Econometrics who did consulting work for various forms of government got a letter offering work but asking tons of hypothetical questions. He soon realized the questions were from a take-home exam; a student had mailed him for the answers. In turn, the guy messaged the surrounding universities about it. He got a letter back from a professor saying to do the work, as usual, cash the check, and put very specific answers on the test. Two weeks later, the professor wrote back saying they busted the student.