Umeboshi are one of the best antidotes to the party season. They're both aspirin and apple, easing the pain, alkalizing the bloodstream, and keeping the doctor away.
These pickled 'apricots' are (to quote) "the culinary equivalent of a cold shower... The abrupt, searingly tart, tangy, salty taste jolts the stomach awake, sandpapers off any staleness from the taste buds and gets the day off to an unforgettable start."
Ume-hachi has a number of dedicated umeboshi boutiques around the city. This branch (in Kita-Aoyama) feels as refined as a wagashiya or tea shop. What makes it even more remarkable is that it's hidden away at the back of a very unprepossessing downmarket supermarket.