Member Rara Avis
Unlike my English compatriot, I absolutely hate have anything in a pocket. I'm sure that's a holdover from my military days (Marines do NOT have little bulges, though I'm told big bulges are acceptable). I might carry paper money in my right trouser pocket, but that rarely qualifies as a true bulge. I never carry coins, both because of the bulge and the fear people will hear me coming.
My key chain includes a quick-release hook, which attaches to either my camera bag or fanny pack (or the shiny metal bars of a shopping cart). The bulk of the camera bag is consumed by the latest paperback, leaving just enough room for my wallet and, sometimes, a check book. The little pocket designed for camera lenses holds emergency aspirins and the like. A pen and a dozen 4x5 index cards for quick notes (not ruled, of course) pretty much rounds out the inventory.
I travel light. Something anyone who drives a Miata learns to do very quickly.