MPlayer OS X is project based on MPlayer (The Movie Player for Linux) for Mac OS X. It consist of compiled binaries of mplayer and mencoder, separate GUI for mencoder and standalone Cocoa player application based on mplayer binaries.
After installation you can simply (by Drag&Drop) play almost all 3ivx, DivX 3,4,5 and other codecs files. Rendering of very nice text-based subtitles is also supported.
For Mac OS X 10.4 (Tiger) only.