After the success of MiniPlayer for iOS I decided to develop the OSX version. MiniPlayer lets you control and search your Music with all the most popular Apps and Music Services. It supports iTunes, Spotify, Rdio and is extensible to any other Application you like with Plug-Ins. You will love to listen your Music thanks to its simple and beautiful UI made by @Surenix.
Three Themes are available : Dynamic, Black and White.
Visit the online help page if you have any question.