http://www.wavpack.com/
WavPack 3.94 Features:[list]4/15/2002: A highly tuned predictor has been developed and incorporated into all new high modes for both the lossless and the new hybrid compression options of WavPack. For pure lossless compression, the old high setting is now the default and is still the recommended mode, but in cases where the minimum possible file size is important, the new high mode gives about 1% to 3% better compression. In the hybrid mode the new high setting additionally improves the audio quality of the lossy files. Also, by popular request, the winamp plugin now uses the .wvc files for lossless playback of hybrid files (although a new configuration option allows the user to turn this off if desired). Finally, all three programs now display their batch progress status on the title bar for easy monitoring when minimized.