ironchef, when I was in Hawaii, my Chinese friends would take hot mustard and mix it with soy sauce to use as a dip with some zip for dim sum. They also would do that and pour it over other kinds of food if it was too bland. (they were northern Chinese by-way-of Taiwan if I remember correctly). Thus you get a similar zip in your food without using a Japanese ingredient! Like most of you, I've only had the green stuff (I refuse to call it Americanized since it has no English on the packaging, so I assume Japanese can't afford the real thing either!). My addition to uses is it is great in salad dressings. I add a dolop to ranch dressing and make a slaw with it, or a dab to vinegarette.