Bonk is a an audio compression program that operates in both lossy and
lossless modes. The compression method Bonk uses is quite simple compared to
other lossy formats such as MP3, and is based on speech compression techniques.
It is nevertheless capable of producing a high compression ratio while
maintaining good sound quality. 

In lossy mode, it averages 14:1 compression while remaining almost perceptually
lossless. This corresponds to 95 kbps for high quality audio. 

In lossless mode the original audio file can be recovered exactly. Lossless
mode typically achieves around 2:1 compression. 

WWW: http://yoyo.cc.monash.edu.au/~pfh/bonk/