One is Konbu, tangle in Englsih. Before cooking rice, put Konbu into a rice cooker so mineral of Konbu make the rice tasety.
Second is juice of grated Daikon(raddish). Adding two spoons of the juice into two go. It makes the rice tasty and soft and sticky texture.
In summer season, poring 2～ 3 drops of vinegar into rice cooker after washing prevents rice from going bad.
These are small trivia, so why don’t you try them?