Here are some pics of my favorite cob! It was the first pipe I ever bought, and it was the only one I smoked for the first 3-4 months of the pipe obsession. I don't smoke it as much now, but when I do it's like coming home. It's the pipe I use to try new tobaccos, because this is the best they can ever taste or smoke.
It's a bent great dane egg. Clenches like a dream, feels natural in the hand, and produces billows of smoke. I let a very thick cake form in it, eventually to the point that I couldn't get my pinky in there. I've since reamed it back, but left a nice thick conical cake in the bottom of the bowl so that the airway now meets in a big mass of cake like the bottom of a briar. Though some caution against cake in a cob, I'm planning on doing this to all my cobs. At the very least, dig out any dottle after your smoke, but shake a good bit of ash around in the bowl, allowing it to coat the voids between the bowl walls and the pine airway. Eventually the bottom of the bowl will fill with a plaster-like pipe mud of ash and moisture, and be rock solid!
See how you can tell where the bottom plug has colored around where the airway protrudes into the bowl? Super cool!