OggQuicklook

OggQuicklook lets you preview ".ogg" audio files in the Mac OS X Finder. Set a custom hotkey to trigger OggQuicklook, then launch its background process.

The background process sits quietly out of the way, using no CPU, until your custom hotkey is triggered while using the Finder, at which point it springs forward instantly to play the selected Ogg audio file. OggQuicklook can also automatically install itself as a login item to ensure instant previewing of .ogg files any time you are working in the Finder.