old story, but still intriguing...

In that old battle of the wills between young people and their keepers, the young have found a new weapon that could change the balance of power on the cellphone front: a ring tone that many adults cannot hear.

"When I heard about it I didn't believe it at first," said Donna Lewis, a technology teacher at the Trinity School in Manhattan. "But one of the kids gave me a copy, and I sent it to a colleague. She played it for her first graders. All of them could hear it, and neither she nor I could."