RichFLV

RichFLV is a free application that works through the engine running Adobe Air, allowing you to play, edit, and extract content from any FLV-formatted video.

It has an attractive interface, like many of the applications that use Adobe Air, which is divided into three sections: viewer, controls, and editor. While you use the viewer to watch the video that you've loaded into the program, you can access the controls to stop or resume playback and skip ahead or back. In the editor section, you can edit the FLV file's metadata, insert or eliminate starting points, and edit key frames.

From the import/export menus you can extract the video's audio, the video alone, or make screen captures. You can also add in video fragments or an alternate audio track.

RichFLV is a great tool for managing your FLV files.