I'm often delighted by the inventiveness and determination of exam cheats. It would be wonderful were such creativity and enthusiasm put into learning whatever it is that exams are supposed to be assessing but, tragically, the inherently demotivating nature of exams (it's all about extrinsic motivation and various ways they diminish intrinsic motivation) means that this is a bit of an uphill struggle. I particularly like the ingenious but not very smart approaches mentioned in this article:

"One test taker apparently hid his or her mother under the desk, from where she fed the student answers, while in a second case, someone outside the test taker's room communicated answers by coughing Morse code."

Of course, the smart ones are not so easily discovered.

This is an endless and absurd arms war that no one can win. The inventiveness and determination of exam cheats is nearly but not quite matched by the inventiveness and determination of exam proctors. My favourite recent example is the Indian Army's reported efforts to prevent exam cheating by making examinees remove all their clothes and sit in an open field, surrounded by uniformed guards. It is hard to believe this could happen but the source seems reliable enough and there are videos to prove it. I'm prepared to bet that they didn't stop cheating altogether, though. 

I've found one and only one absolutely foolproof method of preventing cheating in proctored exams: don't give them in the first place, and challenge yourself to think of smarter ways of judging competence instead. Everyone is better off that way. But, if you are determined to give them, despite the overwhelming evidence that they are demotivating, unfair, unreliable, unkind and costly, don't make it possible for the answers to be given in morse code.