For all of you who have ever sat in a restaurant and been forced to listen to every word spoken by someone on the other side of the room who thought it necessary to shout into his/her cell phone - someone who was oblivious to the fact that a phone can carry normal amplitudes perfectly well and who obviously believed that other people enjoy having their own conversations drowned out by his/her phone conversation - this one's for you.
Disclaimer: Nothing in this post should be construed as an endorsement of the product advertised at the link!