foobar2000 - An advanced freeware audio player for the Windows platform.
Playlist Machinery - Tools that help you create & organize your Spotify playlists
Audacious - Audacious is an advanced audio player.
Heartbeat - Listen to music with your friends together, on Spotify
DeliPlayer - DeliPlayer is a multi format, free audio player for Windows® 98, ME, NT, 2000 and XP.
Magic Playlist - Get the playlist of your dreams based on a song