Free video converter

For quite a while I've been searching for a decent video converter which doesn't lose quality while converting, for free. It'll be mainly used to convert flv to avi, but of course the more supported formats, the better.

Does anybody here have any suggestions, please?

I did use Any Video Converter a while ago, but it keeps losing quality (or am I just doing something wrong?).

Kind regards, Lily

Handbrake does not support AVI, but MPEG Streamclip does

Squared 5 - MPEG Streamclip video converter for Mac OS X

For flv support MPEG Streamclip needs the codec pack Perian installed

Perian - The swiss-army knife of QuickTime® components

You might also want to check out Adapter. It's free, does FLV and what not as well. Adapter - Free Image and Video Converter for Mac and PC