Music and media companies are pinning fresh hopes for reviving their businesses on a small ribbon that Facebook has begun putting on user profiles called the "ticker."
The new, slim stream of updates automatically lists users' activity on apps made for listening to music, watching movies, reading news and playing games after users consent to continuous sharing just once.
Clicking on your friends' items in the ticker can lead to automatically being signed up for free trials on services such as music plans Spotify and Rhapsody, many of which may eventually ask for a monthly fee.
While the feature is billed as a way of fencing off a huge volume of information on what you're doing, for the businesses involved, this way of sharing is a giant viral marketing machine.