I don’t know about you, but I almost never carry a sharpening stone around with me. I may have one in a kit, or my BOB (Bug-Out-Bag), but sometimes, when you’re out and about, it’s nice to bring back that edge to your knife, because a sharp knife is a safe knife. A sharp knife gives you better control while cutting, and of course, it’s more efficient.
Basically, all you have to do is turn an empty ceramic coffee cup upside-down and place it on a table top. Most cups are glazed only on the upper portions and perhaps a recessed bottom, but there is usually a bare ceramic ring exposed that provides just the right abrasion for your blade. My Spyderco Endura has some pretty tough AUS-6 stainless steel that takes a bit of effort to sharpen, but carbon steel blades work quickly. Of course a crowning final touch would be to strop your blade on a hearty pliable surface like a leather belt to set the edge.
I’ve heard that others have used the frosted edge of a car window, or shiny finished cement, but I find that cups have the right abrasion, consistent surface, and can be found quite easily. Just hold the cup by the handle with one hand for stability and with the other hand hold your blade at about a 20 degree slant for a double-sided edge, or at a 40 degree angle for a single single-sided edge.
After your next morning Joe, turn over your cup and give it a try. Just don’t scare the folks around you…