I find class definitions even more difficult and imprecise than folk definitions. I know a former steel-worker with a Masters in English and someone with an engineering degree who is a very successful plumber. Many people who might be considered middle class themselves have distinct working class antecendents just one or two generations back. It's all about roots, innit?

On a totally different tack - I was watching a Harry Potter DVD yesterday with my kids, in a rare moment of repose after a hectic festival weekend, when it occured to me that here is a bastion of Steamfolk and Steampunk. Some wonderful outfits!