Going back into the Art Bell late 90s of C2C, David John Oates was a show regular.
I'm kind of agnostic on the subject, but I remember it being damned entertaining with a few examples that were hard to explain away. My most clear memory was a little kid crying and played backwards you could make out the sentence "help me out".
The theory was that sunconscious (sp) thoughts were able to be extracted from a sound byte reversed.
DJO and Art had a falling out and he was banned from Coast evermore. Although he is based in Australia, it would make for a cool show.
http://www.reversespeech.com/home.htm