Somewhat useful Files and Links
Xvid codec 1.1.0b1 Koepi 2005/01/16 - To play Xvid contents.
A-L playback pack 2004/09/25 - To play .mkv and .ogm files.
Vobsub 2.23 - To play softsubbed files on older systems.
AC3 Audio Filter Pack - To play files with AC3 sound.
AAC parser - To play files with AAC sound.
DivFix - Don't share a divfixed file! ever ever!
Minirp - A cool and small rm (yeah i know...) player.
WinMD5 - A windows easy-to-use MD5 checker.
Zidrav 3.5 - Useful patching tool
If you want a working player that actually uses all the codecs and
filters you've installed, I can only recommend Zoomplayer
or
TheCore Mediaplayer.
An alternative is the open-source VideoLAN
player, which uses
its own set of built-in filters to play almost everything, and works
on nearly all platforms.
You need another codec than those ?
Try http://www.divx-digest.com
or http://www.doom9.org