GB Counties (States) Data (more specific than the countries?)

Here is a list of counties for GB http://en.wikipedia.org/wiki/ISO_3166-2:GB

They're not categorised by country as I don't think that's possible at present?

I'd recommend using this data over the country list pull request (https://github.com/jim/carmen/pull/27) for now as they are more useful, although our postal service has plans to deprecate them in 2013.