Cold somen, as we were taught how to eat it. The idea is, you pick up only a mouthful with your chopsticks from the ice bath, dip it in the soup base, and slurp. The key is to make lots of noise because apparently the Japanese feel that if you sound like you're eating a savoury meal, it'll taste like one too.
It's funny how many North Americans claim to love Japanese food, without having any kind of understanding of what it really is. I'm not claiming I do, but we do have a Japanese person in the family, and after a few visits to Tokyo, I have a good idea of how bland, boring, and completely unfulfilling Japanese cuisine can be. If you want a satisfying meal, with heart and soul, eat Chinese food.