Originally Posted by ONS

WinFF is a cross platform batch GUI for FFMPEG. It will convert most any video file that FFmpeg will convert. WinFF does multiple files in multiple formats at one time. You can for example convert mpeg's, flv's, and mov's, all into avi's all at once.

AVI to DVD, AVI to FLV, AVI to MPG, AVI to WMV, AVI to XviD, DivX to DVD, DivX to FLV, DivX to MPG, DivX to WMV, FLV to AVI, FLV to DVD, FLV to FLV, FLV to MPG, FLV to WMV, MPG to AVI, MPG to FLV, MPG to WMV, VOB to AVI, VOB to FLV, VOB to MPG, VOB to WMV, WMV to AVI, WMV to DVD, WMV to MPG, WMV to XviD

WinFF is open source and cross platform written in Free Pascal and Lazarus.

http://biggmatt.com/winff/