Is there a website to check all media codecs?

Ubuntu should be setup so that when a media type is first-played then Ubuntu will guide the user to install the appropriate codecs via the internet (if they are not already installed). Installing the two ubuntu-restricted-* packages from the Ubuntu Software Centre or command-line should be sufficient:

• sudo apt-get install ubuntu-restricted-addons ubuntu-restricted-extras

I'm sorry that I don't know of a test site with media samples, but perhaps we should set one up to help Ubuntu users? (The snippets would have to be legally free/libre before they could be hosted, which is going to be much harder to acquire unless they are encoded specifically for the purpose).