Rice Cooker Polenta

I wanted to make polenta tonight, but after I read recipes in a couple different cookbooks that involved stirring for 30-60 minutes, and thought there might be an easier way. The Joy of Cooking recipe steams in a double boiler, so it occurred to me that a rice cooker might work. It turns out that it wasn't an original thought, plenty of others have done it. I adapted some of the recipes I saw and came up with this. It worked out pretty well, but could use some more flavor. Parmesan would be the easy thing to add at the end.

1 cup corn meal (½ cup coarse, ½ cup fine)
4 cups water
1 tsp. salt
2 tbl. butter

Stir all ingredients together in the rice cooker. Close the lid and press the button. Stir it a couple times to make sure it's not too clumpy, and let it sit on "keep warm" for a while after the cooking cycle finishes.