There's no question that the Internet has changed global music culture, and Spotify's new Serendipity feature offers clever, beautiful proof. The nifty tool shows when two people are streaming the same song at the same time, from Ellie Goulding's 'Burn' in England and Spain to Hozier's 'Take Me to Church' in California and Australia. It's accurate to one-tenth of a second and shows songs played during a period of one hour.

What's perhaps most interesting about Serendipity is not what it suggests about song trends, but what it says about music distribution. Especially when juxtaposed with Forgotify (which shares Spotify's collection of four million songs that have never been played), Serendipity reveals quite a bit about discovery today. Just because Spotify users have access to thousands of songs doesn't mean they all get heard.