Free Transcode Software
MeWiG is a cool open source program based off of mplayer to _easily_ transcode video files in Windows:
http://mewig.sourceforge.net/
It doesn't depend on Windows codecs, so it nets out to be easier to install, at least for me. Also, it does xvid / mpeg4 2 pass encoding with a single checkbox! Great for converting files into proper formats for DVD-divx players...