Kids turn "teen repellent" sound into teacher-proof ringtone: "Cory Doctorow: Kids in the UK have co-opted an annoying noise sold to retailers as teenager-repellent and turned it into a ringtone. Mosquito is a high-pitched sound 'audible only to teenagers' sold by Britain's Compound Security. It is sold to shopkeepers to use as a teenager repellent -- the idea is to play it loudly in and around shops and 'chase away those annoying teenagers!!!' The kids have reportedly converted the high-pitched noise and turned it into a ringtone, which, being inaudible to grownups, can then be used to receive texts and calls in class without alerting teachers. This is either a magnificent hoax or just plain magnificent -- either way, I love this Little Brother Watches Back parable. Schoolchildren have recorded the sound, which they named Teen Buzz, and spread it from phone to phone via text messages and Bluetooth technology. Now they can receive calls and texts during lessons without teachers having the faintest idea what is going on. A secondary school teacher in Cardiff said: 'All the kids were laughing about something,"