As I learnt from http://wiki.debian.org/MultimediaCodecs Ubuntu's Medibuntu has a Debian counterpart that provides multimedia related with "unpure" licences or other legal problems locking them out from the main repositories:
source.list-snippets can be found right there.
As this is article is a link note anyway, let's continue with other interesting deb sources:
# Google Chrome
deb http://dl.google.com/linux/chrome/deb/ stable main
deb http://deb.opera.com/opera/ stable non-free
# deb http://deb.opera.com/opera-beta/ stable non-free
# Virtualbox. Change squeeze to lenny, hardy, lucid, ... as needed
deb http://download.virtualbox.org/virtualbox/debian squeeze non-free
I think I might maintain and extend this list a while ...
From: IBCL BLog.
Originally posted: 2010-09-13