Len,
It was a tiny bone, one of the 200-odd bones in each foot. I was kneeling down, resting most of my body weight on the left foot, when I heard a snap that came up through my spine and rang between the ears. No pain. Next day, the foot was tender in one spot. Went to a podiatrist but she said, "Nah... you can put weight on it. You didn't break anything! You don't want to waste money on X-Rays do you?"
Fast forward five years and my body is doing a great job of expunging the bone from my body. Its just below the surface. You can feel it with your finger. When I work in my crappy work shoes (like I did for eight hours today) it's sore all night. Tomorrow I'll wear my fancy New Balance walking shoes and it will calm down for a day.
What weirds me is, the other end of the bone must be connected to something. In fact, there should be two connected ends somewhere in there with a break inbetween. This may call for an MRI.
Oh well. I could use a couple weeks off.
Gotta get two major projects done first!