Other than actually activating your core (and shooting for intensity over duration), the key to making planks not suck is to keep your mind busy, whether that's lifting limbs, walking around, or moving weights.
This exercise will hammer the trunk when you maintain a rigid plank. And once you've got that down, you can raise the difficulty by increasing the load or moving the weight in front of the hands.
If you're a bodybuilder and you've spent your weightlifting life doing sets of 8,10, 12, etc., doing singles will absolutely blow you up. A terrific idea and a terrific program that'll raise you head and shoulders above the competition.