Found over on the new Freshmeat section for OS X: Whamb. It plays CDs, mp3s and Ogg files. It is also skinnable and has its own version of playlist sharing over Rendezvous. Pretty slick. There's also a way you can set up a server sharing out playlists over Rendezvous on Linux.

My favorite skin so far is the one shown on the home page. It fits so nicely in the corner of my screen.