Hi chunkeymonkey, in Japan we usually make a couple of cups of rice at once. Then whatever is left over is stored in the fridge or freezer. Rice can store for about a week in the fridge. When we put it in the freezer, we make them into single portion sizes. Wrapping them with plastic wrap in little rectangles so it stores easliy in the freezer. You can put the little rice rectangles in a ziplock bag to keep them together for more organization If you're using long grain rice, maybe it's easier to use small sandwich bags instead of plastic wrap.
Hope this helps out a bit with how to do individual rice servings.
Oh I have a great reheating tip for rice. Put it in a bowl or plate (something microwavable), get a papertowel, wet the papertowel and cover the rice with it. Place the covered rice in the microwave for about 2-3 minutes depending to how strong your microwave is. The rice comes out steamy and nice, just like freshly made rice.
i use 3/4 of a cup to make one portion size, no idea if this is the correct portion size but its enough for me while not being a huge amount on my plate