I like to have some background music when I am not doing anything demanding complete concentration. I practically never use Rhytmbox or Amarok for playing music, as there are some simple text mode applications that fully answer to my needs.
At the moment, my favourite music player is mp3blaster. It uses a nice ncurses interface and is simple enough to use.
Most probably mp3blaster can be installed from the package repositories of the distribution you use.