Open Question: What Program would you use to RIP the audio track out of a video file so you can play them on your MP3 Player?

I need some suggestions on a software package which can RIP the audio track out of various format video files to an MP3 file for use on an audio only MP3 player. Sometimes I don't like to haul my Zune around so I just use my older audio only player, but it can't play my music videos. Any Suggestions appreciated.