I have been training neck this year with great results and I have not seen anyone else doing this.
I have a medicine balls from very small up to 20 pounds. Mine are soft sand fill and they work best but the harder ones work but are less comfortable.
I lay down on a bench with my head hanging off the edge. first, I place a ball on my forehead with my hands on the sides to balance. I then turn my head to the right while using my head to keep the ball tracking the circumference of my head until I am looking over my shoulder. My head has turned and now a but lower than it was in the middle position. I then slowly turn my head back toward the center and raising it up at the same time. I then proceed to the other side in the same fashion. I continue to rotate in this manner until fatigue sets in.
After this set I flip over and place the ball on the back of my had with hands on top (you are much stronger this way) and rotate my head to the left and right while moving my head up and down.
This works great and I find it is really easy on the neck.
TIP: I find that if I extend my neck as far out as possible during the exercise it makes it more comfortable and it also makes the exercise harder (so you can use less weight).
My last tip is shrug motions. I always hated doing shrugs as a kid. Why? I always trained too heavy (just like 99% of people). Training much lighter (I don't go heavier than 50 pound dumbbells or use a cable machine) and my traps get a great pump and are growing.
