I am annoyed every time I read in the paper some utter idiot saying "lie-detector test". You'd think the fact that lie detector tests are as reliable as sacrifices to Cthulu would have gotten around by now (it was discussed publicly during the Watergate hearings in the early 1970's -- and no one has since established that they are of any use at all other than as a bluff by a policeman trying to elicit a confession.
Youtube has many videos on how to beat polygraphs. My friend Willie has only been asked to take one, and he showed up with a machete and a live chicken and a few candles -- when asked why, he said, "You invoke your god, I invoke mine. I'll just use this desk, here." He put the chicken on the desk, and over protests, held it in place as he got out the machete, and was chased from the room by an outraged administrator. His response to his boss? "You should pick calm, thoughtful people next time."
Further notes here.