VLC has in-built codecs which includes (MPEG-1, MPEG-2, MPEG-4, DivX, mp3, ogg, ...) as well as DVDs, VCDs, and various streaming protocols. To see the full list look here: http://www.videolan.org/vlc/features.html which is a damned site more than divx player can do.

Many files are in AVI format which does not necessarily mean DivX!!! Ørbital seems to know little about all the various formats of avi & other video formats. Not taking anything at all away from divx player which is great.

http://www.videolan.org/vlc/ (choose nearest mirror site) It's free & no catches for turning pro or anything, & it plays almost all formats except the odd M$ file such as the odd wmv file.