Youtube to MP3 is a simple but effective tool for extracting audio tracks from YouTube videos.

It's a free browser plug-in for Firefox which allows you to download audio instantly in Firefox using the Video2mp3.net website. Once installed, Youtube to MP3 works by generating a link next to the clip you're viewing which takes you to the Video2mp.net website where your audio file will be downloaded in MP3 format. Note that despite the name, apart from YouTube, Youtube to MP3 works with MyVideo, Clipfish, Sevenload and MySpace videos.

The actual process is a bit long-winded because once you click download, you have to wait for the Video2mp3.net site to process it, then verify it and finally convert the audio to MP3. After that, there's a 20 second wait before you can actually download the file. There are also a series of annoying ads that plague you on the Video2mp3.net website as you download files.

It can only save in MP3 format, but you can always use a third party application such as Handbrake to convert it to another format afterwards.

Youtube to MP3 is fast, effective and a Firefox friendly way to extract audio from your favorite videos