The K-Lite Mega Codec Pack is a free software bundle which includes latest recent codecs and directshow filters to play most video files. Includes QuickTime Alternative, Real Alternative, BSplayer, Media Player Classic, Lame Encoder, DivX, Xvid and many others.

*K-Lite Mega Codec Pack 1.36
*K-Lite Codec Pack 2.52 Full/Standard/Basic
*Quicktime Alternative 1.60 Beta 3

http://www.codecguide.com/