Hi, I know this is an old thread but I came across it when I was looking for new recipes for my rice cooker. One of the most simple things I use my rice cooker for is to steam fish. I start my rice and while it is cooking I make an aluminum foild bowl just big enough to hold the piece of fish I cook (usually a salmon steak). I then place the salmon in the bowl, season and place in the rice cooker when the rice is half way through it's cooking cycle (about 10 minutes).

I usually season the salmon with some soy sauce, chinese cooking sherry, ginger and when it's done I throw some cilantro on top.

By the time the rice is done cooking the fish is perfectly steamed.