Links
 
There are links to competiting products, as I want you to use the best available products. Please note that I do not have tested all these components, so use at your own risk.

FFusion

The FFusion Project. This is the project where the avi importer will be merged.
http://aldorandenet.free.fr/codecs

Libraries and other related Open Source Projects

The XviD project
http://www.xvid.org

The x264 project
http://developers.videolan.org/x264.html

The ffmpeg project
http://ffmpeg.sourceforge.net/index.php

Other Useful QuickTime components

The Perian Component
http://www.perian.org

The DivX Component
http://www.divx.com/divx/mac

The 3ivx Component
http://www.3ivx.com

The x264 Component
https://developer.berlios.de/projects/x264qtcodec

The AC3 Codec
http://trac.cod3r.com/a52codec

Other Links

afreecodec.com
www.afreecodec.com