Linux: There are lots of music and media managers for Linux desktops, and the Music Applet controls almost all of them. It places helpful notifications, button controls, track time and rating data in a convenient corner for your listening pleasure.
Many distributions carry Music Applet in their repositories, so installing should be a simple matter of searching out music applet in your software installer of choice. Once installed, right-click on your GNOME panel, hit "Add to Panel" and select the Music Applet. The applet recognises and controls VLC, Banshee, Amarok, Rhythmbox, Exaile, XMMS and others, but can be set to control a "preferred" player if you've got more than one open.
Granted, some players, like Banshee, already offer control and notification options for the Linux system tray (also known as the "notification area"), but Music Applet is far more configurable and multi-purpose. The app's maker has already started work on a newer version of Music Applet, Panflute, to target the next release of GNOME desktops, but for now, Music Applet is a pretty good music managing solution. Music Applet is a free download for Linux systems (running GNOME desktops) only.