Playlist Machinery - Tools that help you create & organize your Spotify playlists
Playmoss - Create playlists from YouTube, Vimeo and SoundCloud
Magic Playlist - Get the playlist of your dreams based on a song
podsync - Simple and free service that lets you listen to any YouTube or Vimeo channels, playlists or user videos in podcast format
Noiseblend - One-tap music for every occasion, with Spotify Premium
Audioship - Upload audio to YouTube or Facebook