rice balls work well if you make them with asian sticky rice (shortgrain). a children's staple in korea, the kids always take them on school picnics, mothers love to outdo each other with who makes the best rice balls! usually they do chop up veggies, tiny bits of scrambled egg, meat, seaweed, etc and mix it in but i dont' see why you couldn't do them with just balls of rice. very yummy!