Playmoss - Create playlists from YouTube, Vimeo and SoundCloud
Magic Playlist - Get the playlist of your dreams based on a song
Playlist Machinery - Tools that help you create & organize your Spotify playlists
Spotalike - Spotify playlist with similar songs, according to Last.fm
Audioship - Upload audio to YouTube or Facebook
TunesToTube - What does TunesToTube do?