Cabrio is an MP3 player that only uses a small amount of space on your Mac.
It's possible to use the drag-and-drop method to add MP3 files to the play list, or go to File and Add MP3 File. Use the available skins or download some from the home page. You can even make your own. Check the home site for information on creating them.
Just add your favorite MP3s, set the preferences and skin style, and you're ready to enjoy the music while you work.
For more detailed information, including on updates, please read the documentation or visit the home page.
Requirements are: a PowerPC, system 7.5 or greater (MacOS 8.0 or greater recommended) and 8MB of memory.