Wouldn't it be cool to know who was listening to the same song you were at the exact same time?
Sometimes it's scary when the person in the car right next to you is mouthing the same lyrics that you're singing. This probably happens a lot for those who simply listen to the radio, but what about when you've got a CD playing?
If you're listening to the new Anandi or Nickelback CD, there's a good chance there are thousands of others listening with you. But what about when you're playing something like Jethro Tull's "Thick as a Brick" or Blue Oyster Cult's "Cultisaurus Erectus"? What are the chances that someone else is listening to that same CD at the exact same time as you?
Probably small. But it would be neat to know.