EH-Net

A whole website on beating polygraph tests:

http://antipolygraph.org/

Quite a bit of interesting information and background here, including
a downloadable PDF book on beating the polygraph.

My personal experience with these is a bit limited, but I'd be interested
to hear from anyone who has been around them more often.

I saw the Mythbusters try to beet a polygraph. They had no luck. I wonder if they came accross this site when researcing techniques to try....

It appears that we have stumbled across an argument on this  ;D

Here's a post from antipolygraph.org specifically discussing the Mythbusters episode and calling the polygraph guy a quack with a degree from a diploma mill:

http://antipolygraph.org/cgi-bin/forums/YaBB.pl?num=1197009999 (http://antipolygraph.org/cgi-bin/forums/YaBB.pl?num=1197009999)

And for anyone who missed the episode, the relevant bits are here:

http://www.youtube.com/watch?v=mknMAekySjE (http://www.youtube.com/watch?v=mknMAekySjE)

and the beginning of this one:

http://www.youtube.com/watch?v=0zHOz9WhU7c (http://www.youtube.com/watch?v=0zHOz9WhU7c)

Beating a trained polygraph operator is more difficult than all of this (though I admit I didn't read through all of this - it's 1AM and I'm waiting for a scan to finish)

I did a background check for a pen-test recently that required an interview with a 20-year veteran CIA polygrapher.

I, being the curious sort, asked my interviewer once we were done whether the lack of the machine had any impact. 

The answer?

"When you've been doing this for as long as I have, you don't need a machine."

It's one thing to beat a biofeedback machine, but a machine with a trained operator is going to be much more difficult...

I would be curious to see the experiment repeated with someone that (at least theoretically) has some experience with beating the polygraph. Every now and then Mythbusters does a shoddy episode and I think this was one of them.