I loved the idea of dividing your plate into quarters and halves and filling it appropriately. That made it so easy for even the youngest member of the family to 'see' serving sizes. We have some oriental-themed square plates that we use, which also makes it easier to portion food. (For some reason the round edges made it harder).
Now all I need are square plates with raised dividers to make haves and quarters on the plate. My husband ha d good point though- it probably matters how HIGH you stack teh 1/4 of the plate!