Buckwheat is one of those things you find lurking with the other unusual whole grains in places like health food shops. It is not actually a true grain at all, but the seeds of a plant related to rhubarb.
Once or twice as a student, I had attempted to cook buckwheat by boiling it like rice, but it tended to just turn into an unappetising mush.
When I bought a rice cooker, I went looking for books on how to cook different grains in it. I discovered The Ultimate Rice Cooker Cookbook. And therein, I discovered the secret of how to cook buckwheat without turning it to mush: just add an egg or two.