Plug - Lightweight OSX player for Hype Machine
Playlist Machinery - Tools that help you create & organize your Spotify playlists
Magic Playlist - Get the playlist of your dreams based on a song
Spotify.me - Beautiful analytics on your Spotify listening habits 🎧
Playlist Hunt - Playlist Hunt is one of the best applications for Apple users to get the best music through it.
Vinyls - Vinyls is a music player that lets you listen to your music without any complicated setup.