On installing iTunes 4.8 (iPod not required), I discovered that an iTunes Toolbar had appeared as one of my Start Bar Toolbar choices.

If you enable this, and minimise iTunes, a "Mini-Player" appears next to your icon tray. Unlike Winamp (for example), this will run on a single mouse-click. There is a "hidden" left-click menu accessible from the top-right icon (only) with further options.

YMMV - as you may find the amount of TaskBar "real estate" required for this Toolbar incovenient.