There are a plethora of pubs in Tokyo where you can enjoy good sake, but all too often we only read about those in the center of town. The truth, of course, is that there are plenty of great venues outside the Yamanote loop and beyond. Here are a few worth the short or midrange trip:
Tempura Arakawa is a five-minute walk from Higashi Jujo Station on the Keihin Tohoku Line. Located on the ground floor of an apartment building, it seems an unlikely place for a purveyor of fine tempura and sake, but that's exactly what it is. A huge sake refrigerator reassuringly greets you upon entering. The interior is polished, slick and refined.
The main focus here is on Juyondai, but the owner is fairly keen on giving sake recommendations, so feel free to put yourself in his hands. You can learn a lot about sake at a place like this.