Yes, there is. A FLV Converter can help you out. I just know such a FLV Converter which can convert FLV to MP4, FLV to AVI, FLV to WMV, FLV to MPEG etc.
It can also easily convert video files to some popular audio formats, such as WMA, MP3, M4A, AAC, etc.
You can download it here: http://imoviesoft.com/packages/imovie-flv-converter.exe
