Life is too short to listen to crappy digital music. So I recently decided to begin ripping all of my newly purchased CDs into FLAC, the Free Lossless Audio Codec. Music files in FLAC format sound better than those using lossy compression formats such as MP3--plus, FLAC is an open standard. The only downside is that my 80GB Apple iPod doesn't play FLAC files. Happily, RockBox can fix that.
http://www.pcworld.com/article/id,136299-c,freeware/article.html