Muzzy - it’s a tiny and gorgeous iTunes companion that lives on your menu bar. For Mac OSX, its free!
SpotiMy - Play/Pause and Next/Previous functions for Spotify directly on your Menu Bar!
Skip Tunes - Control iTunes, Spotify, or Rdio from your Mac's menubar
Owlead - Grow your Twitter with valuable followers, effortless
Plaaying - Share, control, and keep on Plaaying music on your Mac.
Tabler - Admin panel made simple