Spotify - Map shows when two people play same song at same time
PreFlight - Preflight is an Automated Web Testing tool. Allows everyone to automate Web UI tests.
SoundCloud - Enjoy music & follow favourite artists
AbTest.io - A free url shortener with A/B testing features
Last.fm - The world's largest online music service. Listen online, find out more about your favourite artists, and get music recommendations, only at Last.fm
Marpipe - Automate Your Ad Testing, Optimize Your Creative