Takadanobaba: Izakaya
Wasshoi (Takadanobaba: Izakaya)
Open 4pm-5am daily.
late: Open late
Sun: Open Sundays

This cheap and cheerful late-night izakaya serves decent yakitori and izakaya fare and very cheap beer. The sprawling dining areas are usually crowded with Waseda students.

Shinjuku-ku, Takadanobaba 1-3-13.
東京都新宿区高田馬場1-3-13 第2天台ビル2F
Tokyo Beyond Sushi - the guidebook
Tokyo Beyond Sushi
Explore the hidden side of Tokyo dining
Charcoal-grilled pork on skewers, udon noodles in curry-flavored soup, octopus dumplings, deep-fried beef cutlet -- there's a whole world of exciting food in Tokyo that food-loving visitors often miss out on.

This book will introduce you to more than twenty of Japan's favorite specialty foods that are less well known abroad, along with a guide to the best places in Tokyo to try them and expert tips on what to order. From Bento.com.
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Venue listing from Bento.com5 Star Rating: highly recommended