Another alternative for those business cards is the plastic sleeve pages that office supply places sell with slots for each card and punched for a three ring binder.
I too kept a notebook with tabs for different subject matter/doctors and those pages for business cards and carried that with me to every doctor's appointment. As you all know, each appointment with a new doctor requires the patient to fill out forms and provider/insurance information, so if you have your notebook handy, no need to look up phone numbers, dates, policy #s, etc. It was a life saver.
Deb