To push its new author-narrated crime show Murder by the Book, Court TV is installing narrow-band "audiobeam" sound projectors in bookstores that focus whispery monologues at individual customers. " "Hey you, over here. Don't turn around. Can you hear me? Do you ever think about murder, committing the ultimate crime?" intones the voice to you, and you alone, or anyone else who walks into the beam. Just in case you scream "Yes! Oh yes!" and attack your fellow book-browsers with joyful homicidal abandon, nearby posters warn that the "mystery whisperer" (gag) is all part of this innocuous effort at "experiential marketing" (double gag). Supposedly, the devices have been installed in Time Warner Center, so enjoy that on your lunch break for this rainy day. The technology involved comes mainly from military use, so it has no chance of accidentally boiling your brains out or anything.