Spotalike - Spotify playlist with similar songs, according to Last.fm
Soundbar - A lightweight SoundCloud player for Mac
MusaicFM - An iTunes like screen saver based on Spotify and Last.fm
Sleeve - Your currently playing track displayed right on your desktop
Bowtie - Bowtie is a desktop accessory that allows you to see and control your music (iTunes, Spotify...
Cumulus - A SoundCloud player that lives in your menubar.