Another candidate would be some sorts of peas. There is a trait called the "caterpillar" or "chenille" pea where the peas sit very closely together in the pod, so they apress each other as they grow (basically the same thing as some beans have, or crowder cow peas). In REALLY extreme cases this can result in peas that are more or less perfect cylinders. It's been a long time (during my college days) since I saw peas that extreme, but they do exist.