As urban legends go, this one about how Anton Webern coded secret wartime information into his music is pretty funny. Once, on an Internet Mailing List that I get, it got taken quite seriously - as it is on the Urban Legends website.
Later I ran across a movie that uses the new-music-as-tool-for-spies concept. It's called The Man with One Red Shoe starring a young Tom Hanks. A remake of a French movie. Pretty funny - but all the reviews said "not as funny as the original."
I couldn't find the original, called The Tall Blond Man with One Black Shoe (imagine the title in French) on DVD . . . until a copy appeared on EBay a couple weeks ago. I ordered it. (The movie is still not available on DVD - this was a bootleg. Bad David.)
My Verdict - the orignal is a little funnier because the star (played by Pierre Richard) is much better at physical schtick than Tom Hanks. Otherwise the movies are very similar. People who are amused by ugly new music will love the "opera" he plays on his violin.
Confusingly, I need to mention another movie - Alfred Hitchcock's The Lady Vanishes. But if I tell you why, I'll have to kill you. Or something.