Theres quite a few media players for OS-X that support
.flac.
Mplayer, VLC, Cog al have native .flac support.
iTunes can play flac files, with a utility called 'fluke'-
http://blowintopieces.com/fluke/
There is also a (dead) project called macamp lite x that has a
plugin for .flac support-
http://arcticlounge.com/maltx/