We love MIT's advertising lab blog, because its unearths all that is wacky, wonderful and weird in the world of marketing and media. they also tend to find an advertising angle for new technology, even when there isn't one readily apparent.
so this one was a leap for them, but of interest to us, since it involves modding a technology used to control and manipulate teens behavior (essentially a "dog whistle" only teens can hear, used to keep them from loitering outside of stores) and co-opted it for their own use. Since most people under 20 can't hear the tone, a few tech-savvy and resourceful teenagers recorded the sound and have been virally spreading it amongst teens as a ringtone. Since ringtones must be turned off while at school, these allow students to hear their phones ringing - right in front of their unsuspecting teachers.
talk about turning the tables on technology. love it.