Rice cookers are extremely convenient steamers. They heat up fast, and shut off automatically when the water has evaporated.

Simply fill the bottom of the pan with 1/2" of water, and set to cook. The food should not touch the water, of course. Use a folding steamer insert (most grocery stores carry them, they go for under $5)

A great way to cook vegetables (potatoes, broccoli, asparagus, cauliflower...) but also fish.

My all time favorite: wrap up a piece of Chilean seabass in wax paper, along with a small dash of olive oil and a teaspoon of sundried tomato pesto. Steam in the rice cooker for 12 minutes. There's practically no cleanup, and it's heavenly!