Help with creation, editing, or playback of sounds, images, or video. Amarok, audacious, mplayer, grip, cdparanoia and anything else that makes a sound or plays a video.
mplayer comes with a script that is supposed to do it, using it's program mencoder. I've had some success with it, but of the few I've done most didn't sync well. The audio was a hair faster, very apparent after 15 minutes or so. Maybe it was the type of divx, who knows.