DietMP3

DietMP3 can significantly reduce or "diet" (30% - 70%) the size of an original MP3 file while retaining almost all of the music quality. This allows you to put more songs onto a CD-R or CD-RW when burning your own discs.
More and more electronic devices support MP3 playback capability, including traditional MP3 players, digital cameras, Palm PDA's, Pocket PC's, and even mobile phones. However, due to lack of memory, most of these devices can only store a very limited number of music files. DietMP3 can compress the size of your MP3 files, allowing you to add more songs to your player without an expensive memory upgrade.