How can I extract audio from a YouTube video?

I would like to hear Linus' talk about Git from youtube on my way to work, which means I'm looking for an elegant way to extract .wav or .mp3 from a YouTube video.

install Youtube-dl and FFmpeg then use the following commandline

Download the video

youtube-dl --extract-audio --audio-format mp3 http://www.youtube.com/watch?v=YOURVIDEO 

optionally use the -k flag to keep the video by default it deletes the video

I have had success with video2mp3.net – it is free and online!

Add the YouTube to MP3 firefox add-on.

I used the Online FLV convertor for this . Just give the url and select way of output you want .

mplayer x.flv -vo null -ao pcm
lame -V2 audiodump.wav talk.mp3

This will extract the audio in wav format and encode it to a VBR mp3 with lame.