RichFLV is an AdobeAir application that allows you to edit FLV files. The application is fairly simple to install since Adode Air makes it simple to download and install the app.
The FLV video editor can read meta data of the video file, it can also read and edit the cue points in the videos. The red slider at the bottom of the application allows you to select and export parts of the FLV file. Saving the cut part just takes seconds.
The app can also change the sound track of the video. You may also convert the sound to mp3 format. Lastly, exporting to swf format is also supported.
The app can be used to extract and mp3 from music video files.