What happens is that if you click on the Tone icon, it sends out an audio tone that will be detected by other audio computers in the room, which would then switch their browsers to the same URL.
Apparently the Google Research team worked pretty hard on this. The first codec sounded so horrible that no one would use it. The second codec was beyond the range of hearing, and some built-in computer microphones wouldn't track it.
This current codec uses a system that most telephone systems use called dual-tone multi-frequency signaling, which is much more pleasant to the ear and much more effective as well.
You can download the extension here if you're interested.
Can anyone think of a use for this?
