Visited Yagicho store in Nihonbashi and bought Kamebushi （亀節）- one kind of dried bonito (Katsuo bushi - 鰹節）.
After that, had wonderful lunch at "Inaniwa udon meshi Kenko Hannosuke" （稲庭うどんとめし 金子半之助）. The restaurant is located at B1 of Coredo Muromachi Bldg. 2, and offers "Tenbara meshi" (天ばらめし) or rice bowl topped with tempura, Inaniwa udon noodle (稲庭うどん）, "Kaisen don" （海鮮丼）or rice bowl topped with sashimi, and so on. The picture is a set of "Tenbara meshi" and "Inaniwa udon noodle", which costs only 1280 yen. You can also eat varieties of toppings including eggs, seaweed, etc. This restaurant I believe is an excellent place not many people know about.
It is always nice to walk around Nihonbashi area, where many traditional Japanese stores with long history run their business with such attractive products and services. Yagicho is definitely one of them (they started their business in 1737!)
You can also find many stores that specialize in local products from various regions in Japan, which are called "antenna shop". You can find nice suveniors and restaurants with local dishes.