by a power switch! All the rice cookers I've owned, always had at least a push-down button to start the rice cooking cycle, much like a push down for a toaster.
Could you please give me a little more detail?
While it's not a good deal in terms of price, the Zojirushi fuzzy logic 10 cup rice cooker may be what you mean - it can be kept plugged in, and even has a timer feature so that you can set it up before you even leave for work, and come home to fluffy perfect rice.
http://www.amazon.com/exec/obidos/AS...092022-5190239