The Beatles are probably the most famous for using it in their songs i.e. "I'm so tired" from their White Album. When played backwards you can hear, "Paul is dead, miss him, miss him, miss him". Many groups used backmasking as for me I think it's cool. Check the link for more iinfo.
Turn me on, dead man; turn me on, dead man; turn me on, dead man...!
I personally love it whether it's fact or fiction. I had a period of time in my life that I was into the occult and followed the freaky Tantric mysticism of the late Aleister Crowley. In addition to being what non-occultists call "a black magician," Mr. Crowley [aka Edward Alexander Crowley] is one of the most misunderstood figures in history. (Some believe he was a walk-in from another planet, and before you pooh pooh it, can you really say that there was no connection between the 1947 Roswell Saucer Flap and Mr. Crowley's demise after many decades of opiate addiction.) It so happens that Jimmy Page spent a small fortune buying up Crowley books in Southern California simply by putting out the word that his groupies could rake in handsome finders' fees for copies of first editions of "Papa's" poetry collections, short stories, plays, and "magickal" books, including that Greatest of Greats, the first edition of The Book of the Law, the Bible of Crowleyanity.
Hearing of this, the Christer freaks got hold of a copy of "Stairway to Heaven," which has had the reputation of a backmasked track. Judge for yourself if at any point Mr. Plant sings the thing that the fools and nutcases claim they hear: "My Sweet Satan." http://www.youtube.com/watch?v=jbNqeDr5mlQ
I do wish to say that I find the track played backward almost mesmerizing and likely to drive one insane if one plays it too often.
My opinion? It starts at 9:06. http://www.youtube.com/watch?v=8T_jwq9ph8k
I'm with you, Pat, in that opinion. Just tell somebody what to hear and they'll hear it. It will be as clear as the man in the moon.