Sorry i haven't had the time to read all of this thread!
However, for what it's worth, i think cards are a good idea for every Brit to carry around.
I imagine a card with all your medical data on which you give to GP's, Doctors etc...this would mean you are in charge of your medical data and if you are in an accident you have it on you so that medical staff will know if you are allergic to anything.
I don't see why the cards cant incorporate data such as passport info.
IMO, this would cut the need for the goverment to hold data on people.
This would help curb these ideas of having all your data stored on massive databases.
By the amount of money the government would save in contracting companies to create databases they ould use the revenue to make these cards free of charge.