Kiri is a wonderful little basement spot in between Hibiya, Ginza and Yurakucho stations. It's a small, square room that can seat about 15-20 people max. There's live music on Saturday's but other nights just master Naito-san's vinyl collection. (Hank Mobley playing when I went in, major points for that.)
The vibe in Kiri is quiet and sophisticated without being snobby. Over 200 bottles of whiskey/scotch/bourbon behind the bar are an added attraction for serious drinkers. Pricey, so bring cash.