Keybase Chat - End-to-end encrypted chat built into Keybase
Annie Music - The easiest way to share good music
Pithos - pithos is a daemon which provides an S3-compatible frontend for storing files in a Cassandra cluster.
SOUNDS - Discover music with friends
Pandora - Pandora Radio is a free (ad-supported) internet radio founded in 2000.
Spotify - Map shows when two people play same song at same time