Momixa - Pick two songs and get the perfect mix
Spotify.me - Beautiful analytics on your Spotify listening habits 🎧
Liveset Database - Database site with tracklists from Dj sets
SpotMenu - Spotify and iTunes in your macOS menu bar
FIEND.fm - "Hot or Not" for music discovery: 2 hrs of tracks in 2 mins
Surface Studio - A brilliant screen for your ideas, from Microsoft