With personal media players (PMP) getting really affordable, consumers are converting their video collection to formats that are supported by their favorite PMP. In my case, I use an iPhone so I convert movies to H.264 or MP4 formats.
There are several tools available to convert videos to other formats and mencoder is just one of them. Personally, I use ffmpeg, also from the same family as mencoder but with a graphical front-end. Anyway, to those who want to convert videos using the CLI, here's a useful Linux.com tip for you.