A rock in the pocket
Back in the 1970s, Dennis Weaver starred in the popular TV series, "McCloud." He played the role of a western law officer who was teamed with a law officer from a big city "back East." Each of them played a perfect counterpoint to the other. At the end of one program, the camera shows the two of them walking away and you hear Weaver say, "There's a rock in my boot." The other character says with an almost parched wit, "It must have fallen out of your head."
I have a rock in my pocket. It is not very big. It is smooth. It was smooth when I got it, and it is even smoother now. Across the surface of one side is the word "CREDO." I received the rock at the end of participating in a June 2004 conference by that name.