Like every popular online service out there -- from OkCupid to PornHub -- Spotify keeps tabs on its users, and especially their listening trends. The popular streaming site's already demonstrated its anthropological power to learn about people through music, and now it's expanding that power to a global scale.
Spotify calls this innocuous use of anonymised data gathering as Musical Map, a thousand playlists each from a different city that represents the distinctive music tastes of its residents. These aren't the most popular songs, mind you -- just the ones that are outliers when compared to other cities around the world.
The result? A strange amalgamation of music you wouldn't necessarily identify with your hometown. [Spotify]