I'm not sure how many of you are familiar with the episode, but Mythbusters attmpted to fool a polygraph "by using pain to try and increase the readings when answering truthfully (so the machine will supposedly interpret the truthful and non-truthful answers as the same.) They also attempted to fool the polygraph by thinking happy thoughts when lying and thinking stressful thoughts when telling the truth to try and confuse the machine. However, neither technique was successful and the examiner Michael Martin correctly identified each guilty and innocent subject. "

Anxious,

In order to successfully employ polygraph countermeasures, one must:

1) Identify the "control" questions; and
2) Augment physiological responses to them at the proper time.

The latter technique is useless without the former. 

The Mythbusters piece provides an excellent example of someone attempting to employ polygraph countermeasures without fully understanding the flawed logic behind the "test."